i386: move mm

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 858 insertions, 0 deletions

diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
new file mode 100644
index 00000000000..730a5b177b1
--- /dev/null
+++ b/arch/x86/mm/init_32.c
@@ -0,0 +1,858 @@
+/*
+ *  linux/arch/i386/mm/init.c
+ *
+ *  Copyright (C) 1995  Linus Torvalds
+ *
+ *  Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
+ */
+
+#include <linux/module.h>
+#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/hugetlb.h>
+#include <linux/swap.h>
+#include <linux/smp.h>
+#include <linux/init.h>
+#include <linux/highmem.h>
+#include <linux/pagemap.h>
+#include <linux/pfn.h>
+#include <linux/poison.h>
+#include <linux/bootmem.h>
+#include <linux/slab.h>
+#include <linux/proc_fs.h>
+#include <linux/efi.h>
+#include <linux/memory_hotplug.h>
+#include <linux/initrd.h>
+#include <linux/cpumask.h>
+
+#include <asm/processor.h>
+#include <asm/system.h>
+#include <asm/uaccess.h>
+#include <asm/pgtable.h>
+#include <asm/dma.h>
+#include <asm/fixmap.h>
+#include <asm/e820.h>
+#include <asm/apic.h>
+#include <asm/tlb.h>
+#include <asm/tlbflush.h>
+#include <asm/sections.h>
+#include <asm/paravirt.h>
+
+unsigned int __VMALLOC_RESERVE = 128 << 20;
+
+DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
+unsigned long highstart_pfn, highend_pfn;
+
+static int noinline do_test_wp_bit(void);
+
+/*
+ * Creates a middle page table and puts a pointer to it in the
+ * given global directory entry. This only returns the gd entry
+ * in non-PAE compilation mode, since the middle layer is folded.
+ */
+static pmd_t * __init one_md_table_init(pgd_t *pgd)
+{
+	pud_t *pud;
+	pmd_t *pmd_table;
+		
+#ifdef CONFIG_X86_PAE
+	if (!(pgd_val(*pgd) & _PAGE_PRESENT)) {
+		pmd_table = (pmd_t *) alloc_bootmem_low_pages(PAGE_SIZE);
+
+		paravirt_alloc_pd(__pa(pmd_table) >> PAGE_SHIFT);
+		set_pgd(pgd, __pgd(__pa(pmd_table) | _PAGE_PRESENT));
+		pud = pud_offset(pgd, 0);
+		if (pmd_table != pmd_offset(pud, 0))
+			BUG();
+	}
+#endif
+	pud = pud_offset(pgd, 0);
+	pmd_table = pmd_offset(pud, 0);
+	return pmd_table;
+}
+
+/*
+ * Create a page table and place a pointer to it in a middle page
+ * directory entry.
+ */
+static pte_t * __init one_page_table_init(pmd_t *pmd)
+{
+	if (!(pmd_val(*pmd) & _PAGE_PRESENT)) {
+		pte_t *page_table = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
+
+		paravirt_alloc_pt(&init_mm, __pa(page_table) >> PAGE_SHIFT);
+		set_pmd(pmd, __pmd(__pa(page_table) | _PAGE_TABLE));
+		BUG_ON(page_table != pte_offset_kernel(pmd, 0));
+	}
+	
+	return pte_offset_kernel(pmd, 0);
+}
+
+/*
+ * This function initializes a certain range of kernel virtual memory 
+ * with new bootmem page tables, everywhere page tables are missing in
+ * the given range.
+ */
+
+/*
+ * NOTE: The pagetables are allocated contiguous on the physical space 
+ * so we can cache the place of the first one and move around without 
+ * checking the pgd every time.
+ */
+static void __init page_table_range_init (unsigned long start, unsigned long end, pgd_t *pgd_base)
+{
+	pgd_t *pgd;
+	pmd_t *pmd;
+	int pgd_idx, pmd_idx;
+	unsigned long vaddr;
+
+	vaddr = start;
+	pgd_idx = pgd_index(vaddr);
+	pmd_idx = pmd_index(vaddr);
+	pgd = pgd_base + pgd_idx;
+
+	for ( ; (pgd_idx < PTRS_PER_PGD) && (vaddr != end); pgd++, pgd_idx++) {
+		pmd = one_md_table_init(pgd);
+		pmd = pmd + pmd_index(vaddr);
+		for (; (pmd_idx < PTRS_PER_PMD) && (vaddr != end); pmd++, pmd_idx++) {
+			one_page_table_init(pmd);
+
+			vaddr += PMD_SIZE;
+		}
+		pmd_idx = 0;
+	}
+}
+
+static inline int is_kernel_text(unsigned long addr)
+{
+	if (addr >= PAGE_OFFSET && addr <= (unsigned long)__init_end)
+		return 1;
+	return 0;
+}
+
+/*
+ * This maps the physical memory to kernel virtual address space, a total 
+ * of max_low_pfn pages, by creating page tables starting from address 
+ * PAGE_OFFSET.
+ */
+static void __init kernel_physical_mapping_init(pgd_t *pgd_base)
+{
+	unsigned long pfn;
+	pgd_t *pgd;
+	pmd_t *pmd;
+	pte_t *pte;
+	int pgd_idx, pmd_idx, pte_ofs;
+
+	pgd_idx = pgd_index(PAGE_OFFSET);
+	pgd = pgd_base + pgd_idx;
+	pfn = 0;
+
+	for (; pgd_idx < PTRS_PER_PGD; pgd++, pgd_idx++) {
+		pmd = one_md_table_init(pgd);
+		if (pfn >= max_low_pfn)
+			continue;
+		for (pmd_idx = 0; pmd_idx < PTRS_PER_PMD && pfn < max_low_pfn; pmd++, pmd_idx++) {
+			unsigned int address = pfn * PAGE_SIZE + PAGE_OFFSET;
+
+			/* Map with big pages if possible, otherwise create normal page tables. */
+			if (cpu_has_pse) {
+				unsigned int address2 = (pfn + PTRS_PER_PTE - 1) * PAGE_SIZE + PAGE_OFFSET + PAGE_SIZE-1;
+				if (is_kernel_text(address) || is_kernel_text(address2))
+					set_pmd(pmd, pfn_pmd(pfn, PAGE_KERNEL_LARGE_EXEC));
+				else
+					set_pmd(pmd, pfn_pmd(pfn, PAGE_KERNEL_LARGE));
+
+				pfn += PTRS_PER_PTE;
+			} else {
+				pte = one_page_table_init(pmd);
+
+				for (pte_ofs = 0;
+				     pte_ofs < PTRS_PER_PTE && pfn < max_low_pfn;
+				     pte++, pfn++, pte_ofs++, address += PAGE_SIZE) {
+					if (is_kernel_text(address))
+						set_pte(pte, pfn_pte(pfn, PAGE_KERNEL_EXEC));
+					else
+						set_pte(pte, pfn_pte(pfn, PAGE_KERNEL));
+				}
+			}
+		}
+	}
+}
+
+static inline int page_kills_ppro(unsigned long pagenr)
+{
+	if (pagenr >= 0x70000 && pagenr <= 0x7003F)
+		return 1;
+	return 0;
+}
+
+int page_is_ram(unsigned long pagenr)
+{
+	int i;
+	unsigned long addr, end;
+
+	if (efi_enabled) {
+		efi_memory_desc_t *md;
+		void *p;
+
+		for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
+			md = p;
+			if (!is_available_memory(md))
+				continue;
+			addr = (md->phys_addr+PAGE_SIZE-1) >> PAGE_SHIFT;
+			end = (md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT)) >> PAGE_SHIFT;
+
+			if ((pagenr >= addr) && (pagenr < end))
+				return 1;
+		}
+		return 0;
+	}
+
+	for (i = 0; i < e820.nr_map; i++) {
+
+		if (e820.map[i].type != E820_RAM)	/* not usable memory */
+			continue;
+		/*
+		 *	!!!FIXME!!! Some BIOSen report areas as RAM that
+		 *	are not. Notably the 640->1Mb area. We need a sanity
+		 *	check here.
+		 */
+		addr = (e820.map[i].addr+PAGE_SIZE-1) >> PAGE_SHIFT;
+		end = (e820.map[i].addr+e820.map[i].size) >> PAGE_SHIFT;
+		if  ((pagenr >= addr) && (pagenr < end))
+			return 1;
+	}
+	return 0;
+}
+
+#ifdef CONFIG_HIGHMEM
+pte_t *kmap_pte;
+pgprot_t kmap_prot;
+
+#define kmap_get_fixmap_pte(vaddr)					\
+	pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), vaddr), (vaddr)), (vaddr))
+
+static void __init kmap_init(void)
+{
+	unsigned long kmap_vstart;
+
+	/* cache the first kmap pte */
+	kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
+	kmap_pte = kmap_get_fixmap_pte(kmap_vstart);
+
+	kmap_prot = PAGE_KERNEL;
+}
+
+static void __init permanent_kmaps_init(pgd_t *pgd_base)
+{
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+	pte_t *pte;
+	unsigned long vaddr;
+
+	vaddr = PKMAP_BASE;
+	page_table_range_init(vaddr, vaddr + PAGE_SIZE*LAST_PKMAP, pgd_base);
+
+	pgd = swapper_pg_dir + pgd_index(vaddr);
+	pud = pud_offset(pgd, vaddr);
+	pmd = pmd_offset(pud, vaddr);
+	pte = pte_offset_kernel(pmd, vaddr);
+	pkmap_page_table = pte;	
+}
+
+static void __meminit free_new_highpage(struct page *page)
+{
+	init_page_count(page);
+	__free_page(page);
+	totalhigh_pages++;
+}
+
+void __init add_one_highpage_init(struct page *page, int pfn, int bad_ppro)
+{
+	if (page_is_ram(pfn) && !(bad_ppro && page_kills_ppro(pfn))) {
+		ClearPageReserved(page);
+		free_new_highpage(page);
+	} else
+		SetPageReserved(page);
+}
+
+static int __meminit add_one_highpage_hotplug(struct page *page, unsigned long pfn)
+{
+	free_new_highpage(page);
+	totalram_pages++;
+#ifdef CONFIG_FLATMEM
+	max_mapnr = max(pfn, max_mapnr);
+#endif
+	num_physpages++;
+	return 0;
+}
+
+/*
+ * Not currently handling the NUMA case.
+ * Assuming single node and all memory that
+ * has been added dynamically that would be
+ * onlined here is in HIGHMEM
+ */
+void __meminit online_page(struct page *page)
+{
+	ClearPageReserved(page);
+	add_one_highpage_hotplug(page, page_to_pfn(page));
+}
+
+
+#ifdef CONFIG_NUMA
+extern void set_highmem_pages_init(int);
+#else
+static void __init set_highmem_pages_init(int bad_ppro)
+{
+	int pfn;
+	for (pfn = highstart_pfn; pfn < highend_pfn; pfn++)
+		add_one_highpage_init(pfn_to_page(pfn), pfn, bad_ppro);
+	totalram_pages += totalhigh_pages;
+}
+#endif /* CONFIG_FLATMEM */
+
+#else
+#define kmap_init() do { } while (0)
+#define permanent_kmaps_init(pgd_base) do { } while (0)
+#define set_highmem_pages_init(bad_ppro) do { } while (0)
+#endif /* CONFIG_HIGHMEM */
+
+unsigned long long __PAGE_KERNEL = _PAGE_KERNEL;
+EXPORT_SYMBOL(__PAGE_KERNEL);
+unsigned long long __PAGE_KERNEL_EXEC = _PAGE_KERNEL_EXEC;
+
+#ifdef CONFIG_NUMA
+extern void __init remap_numa_kva(void);
+#else
+#define remap_numa_kva() do {} while (0)
+#endif
+
+void __init native_pagetable_setup_start(pgd_t *base)
+{
+#ifdef CONFIG_X86_PAE
+	int i;
+
+	/*
+	 * Init entries of the first-level page table to the
+	 * zero page, if they haven't already been set up.
+	 *
+	 * In a normal native boot, we'll be running on a
+	 * pagetable rooted in swapper_pg_dir, but not in PAE
+	 * mode, so this will end up clobbering the mappings
+	 * for the lower 24Mbytes of the address space,
+	 * without affecting the kernel address space.
+	 */
+	for (i = 0; i < USER_PTRS_PER_PGD; i++)
+		set_pgd(&base[i],
+			__pgd(__pa(empty_zero_page) | _PAGE_PRESENT));
+
+	/* Make sure kernel address space is empty so that a pagetable
+	   will be allocated for it. */
+	memset(&base[USER_PTRS_PER_PGD], 0,
+	       KERNEL_PGD_PTRS * sizeof(pgd_t));
+#else
+	paravirt_alloc_pd(__pa(swapper_pg_dir) >> PAGE_SHIFT);
+#endif
+}
+
+void __init native_pagetable_setup_done(pgd_t *base)
+{
+#ifdef CONFIG_X86_PAE
+	/*
+	 * Add low memory identity-mappings - SMP needs it when
+	 * starting up on an AP from real-mode. In the non-PAE
+	 * case we already have these mappings through head.S.
+	 * All user-space mappings are explicitly cleared after
+	 * SMP startup.
+	 */
+	set_pgd(&base[0], base[USER_PTRS_PER_PGD]);
+#endif
+}
+
+/*
+ * Build a proper pagetable for the kernel mappings.  Up until this
+ * point, we've been running on some set of pagetables constructed by
+ * the boot process.
+ *
+ * If we're booting on native hardware, this will be a pagetable
+ * constructed in arch/i386/kernel/head.S, and not running in PAE mode
+ * (even if we'll end up running in PAE).  The root of the pagetable
+ * will be swapper_pg_dir.
+ *
+ * If we're booting paravirtualized under a hypervisor, then there are
+ * more options: we may already be running PAE, and the pagetable may
+ * or may not be based in swapper_pg_dir.  In any case,
+ * paravirt_pagetable_setup_start() will set up swapper_pg_dir
+ * appropriately for the rest of the initialization to work.
+ *
+ * In general, pagetable_init() assumes that the pagetable may already
+ * be partially populated, and so it avoids stomping on any existing
+ * mappings.
+ */
+static void __init pagetable_init (void)
+{
+	unsigned long vaddr, end;
+	pgd_t *pgd_base = swapper_pg_dir;
+
+	paravirt_pagetable_setup_start(pgd_base);
+
+	/* Enable PSE if available */
+	if (cpu_has_pse)
+		set_in_cr4(X86_CR4_PSE);
+
+	/* Enable PGE if available */
+	if (cpu_has_pge) {
+		set_in_cr4(X86_CR4_PGE);
+		__PAGE_KERNEL |= _PAGE_GLOBAL;
+		__PAGE_KERNEL_EXEC |= _PAGE_GLOBAL;
+	}
+
+	kernel_physical_mapping_init(pgd_base);
+	remap_numa_kva();
+
+	/*
+	 * 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;
+	end = (FIXADDR_TOP + PMD_SIZE - 1) & PMD_MASK;
+	page_table_range_init(vaddr, end, pgd_base);
+
+	permanent_kmaps_init(pgd_base);
+
+	paravirt_pagetable_setup_done(pgd_base);
+}
+
+#if defined(CONFIG_HIBERNATION) || defined(CONFIG_ACPI)
+/*
+ * Swap suspend & friends need this for resume because things like the intel-agp
+ * driver might have split up a kernel 4MB mapping.
+ */
+char __nosavedata swsusp_pg_dir[PAGE_SIZE]
+	__attribute__ ((aligned (PAGE_SIZE)));
+
+static inline void save_pg_dir(void)
+{
+	memcpy(swsusp_pg_dir, swapper_pg_dir, PAGE_SIZE);
+}
+#else
+static inline void save_pg_dir(void)
+{
+}
+#endif
+
+void zap_low_mappings (void)
+{
+	int i;
+
+	save_pg_dir();
+
+	/*
+	 * Zap initial low-memory mappings.
+	 *
+	 * Note that "pgd_clear()" doesn't do it for
+	 * us, because pgd_clear() is a no-op on i386.
+	 */
+	for (i = 0; i < USER_PTRS_PER_PGD; i++)
+#ifdef CONFIG_X86_PAE
+		set_pgd(swapper_pg_dir+i, __pgd(1 + __pa(empty_zero_page)));
+#else
+		set_pgd(swapper_pg_dir+i, __pgd(0));
+#endif
+	flush_tlb_all();
+}
+
+int nx_enabled = 0;
+
+#ifdef CONFIG_X86_PAE
+
+static int disable_nx __initdata = 0;
+u64 __supported_pte_mask __read_mostly = ~_PAGE_NX;
+EXPORT_SYMBOL_GPL(__supported_pte_mask);
+
+/*
+ * noexec = on|off
+ *
+ * Control non executable mappings.
+ *
+ * on      Enable
+ * off     Disable
+ */
+static int __init noexec_setup(char *str)
+{
+	if (!str || !strcmp(str, "on")) {
+		if (cpu_has_nx) {
+			__supported_pte_mask |= _PAGE_NX;
+			disable_nx = 0;
+		}
+	} else if (!strcmp(str,"off")) {
+		disable_nx = 1;
+		__supported_pte_mask &= ~_PAGE_NX;
+	} else
+		return -EINVAL;
+
+	return 0;
+}
+early_param("noexec", noexec_setup);
+
+static void __init set_nx(void)
+{
+	unsigned int v[4], l, h;
+
+	if (cpu_has_pae && (cpuid_eax(0x80000000) > 0x80000001)) {
+		cpuid(0x80000001, &v[0], &v[1], &v[2], &v[3]);
+		if ((v[3] & (1 << 20)) && !disable_nx) {
+			rdmsr(MSR_EFER, l, h);
+			l |= EFER_NX;
+			wrmsr(MSR_EFER, l, h);
+			nx_enabled = 1;
+			__supported_pte_mask |= _PAGE_NX;
+		}
+	}
+}
+
+/*
+ * Enables/disables executability of a given kernel page and
+ * returns the previous setting.
+ */
+int __init set_kernel_exec(unsigned long vaddr, int enable)
+{
+	pte_t *pte;
+	int ret = 1;
+
+	if (!nx_enabled)
+		goto out;
+
+	pte = lookup_address(vaddr);
+	BUG_ON(!pte);
+
+	if (!pte_exec_kernel(*pte))
+		ret = 0;
+
+	if (enable)
+		pte->pte_high &= ~(1 << (_PAGE_BIT_NX - 32));
+	else
+		pte->pte_high |= 1 << (_PAGE_BIT_NX - 32);
+	pte_update_defer(&init_mm, vaddr, pte);
+	__flush_tlb_all();
+out:
+	return ret;
+}
+
+#endif
+
+/*
+ * paging_init() sets up the page tables - note that the first 8MB are
+ * already mapped by head.S.
+ *
+ * This routines also unmaps the page at virtual kernel address 0, so
+ * that we can trap those pesky NULL-reference errors in the kernel.
+ */
+void __init paging_init(void)
+{
+#ifdef CONFIG_X86_PAE
+	set_nx();
+	if (nx_enabled)
+		printk("NX (Execute Disable) protection: active\n");
+#endif
+
+	pagetable_init();
+
+	load_cr3(swapper_pg_dir);
+
+#ifdef CONFIG_X86_PAE
+	/*
+	 * We will bail out later - printk doesn't work right now so
+	 * the user would just see a hanging kernel.
+	 */
+	if (cpu_has_pae)
+		set_in_cr4(X86_CR4_PAE);
+#endif
+	__flush_tlb_all();
+
+	kmap_init();
+}
+
+/*
+ * Test if the WP bit works in supervisor mode. It isn't supported on 386's
+ * and also on some strange 486's (NexGen etc.). All 586+'s are OK. This
+ * used to involve black magic jumps to work around some nasty CPU bugs,
+ * but fortunately the switch to using exceptions got rid of all that.
+ */
+
+static void __init test_wp_bit(void)
+{
+	printk("Checking if this processor honours the WP bit even in supervisor mode... ");
+
+	/* Any page-aligned address will do, the test is non-destructive */
+	__set_fixmap(FIX_WP_TEST, __pa(&swapper_pg_dir), PAGE_READONLY);
+	boot_cpu_data.wp_works_ok = do_test_wp_bit();
+	clear_fixmap(FIX_WP_TEST);
+
+	if (!boot_cpu_data.wp_works_ok) {
+		printk("No.\n");
+#ifdef CONFIG_X86_WP_WORKS_OK
+		panic("This kernel doesn't support CPU's with broken WP. Recompile it for a 386!");
+#endif
+	} else {
+		printk("Ok.\n");
+	}
+}
+
+static struct kcore_list kcore_mem, kcore_vmalloc; 
+
+void __init mem_init(void)
+{
+	extern int ppro_with_ram_bug(void);
+	int codesize, reservedpages, datasize, initsize;
+	int tmp;
+	int bad_ppro;
+
+#ifdef CONFIG_FLATMEM
+	BUG_ON(!mem_map);
+#endif
+	
+	bad_ppro = ppro_with_ram_bug();
+
+#ifdef CONFIG_HIGHMEM
+	/* check that fixmap and pkmap do not overlap */
+	if (PKMAP_BASE+LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) {
+		printk(KERN_ERR "fixmap and kmap areas overlap - this will crash\n");
+		printk(KERN_ERR "pkstart: %lxh pkend: %lxh fixstart %lxh\n",
+				PKMAP_BASE, PKMAP_BASE+LAST_PKMAP*PAGE_SIZE, FIXADDR_START);
+		BUG();
+	}
+#endif
+ 
+	/* this will put all low memory onto the freelists */
+	totalram_pages += free_all_bootmem();
+
+	reservedpages = 0;
+	for (tmp = 0; tmp < max_low_pfn; tmp++)
+		/*
+		 * Only count reserved RAM pages
+		 */
+		if (page_is_ram(tmp) && PageReserved(pfn_to_page(tmp)))
+			reservedpages++;
+
+	set_highmem_pages_init(bad_ppro);
+
+	codesize =  (unsigned long) &_etext - (unsigned long) &_text;
+	datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
+	initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
+
+	kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT); 
+	kclist_add(&kcore_vmalloc, (void *)VMALLOC_START, 
+		   VMALLOC_END-VMALLOC_START);
+
+	printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, %dk reserved, %dk data, %dk init, %ldk highmem)\n",
+		(unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
+		num_physpages << (PAGE_SHIFT-10),
+		codesize >> 10,
+		reservedpages << (PAGE_SHIFT-10),
+		datasize >> 10,
+		initsize >> 10,
+		(unsigned long) (totalhigh_pages << (PAGE_SHIFT-10))
+	       );
+
+#if 1 /* double-sanity-check paranoia */
+	printk("virtual kernel memory layout:\n"
+	       "    fixmap  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
+#ifdef CONFIG_HIGHMEM
+	       "    pkmap   : 0x%08lx - 0x%08lx   (%4ld kB)\n"
+#endif
+	       "    vmalloc : 0x%08lx - 0x%08lx   (%4ld MB)\n"
+	       "    lowmem  : 0x%08lx - 0x%08lx   (%4ld MB)\n"
+	       "      .init : 0x%08lx - 0x%08lx   (%4ld kB)\n"
+	       "      .data : 0x%08lx - 0x%08lx   (%4ld kB)\n"
+	       "      .text : 0x%08lx - 0x%08lx   (%4ld kB)\n",
+	       FIXADDR_START, FIXADDR_TOP,
+	       (FIXADDR_TOP - FIXADDR_START) >> 10,
+
+#ifdef CONFIG_HIGHMEM
+	       PKMAP_BASE, PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
+	       (LAST_PKMAP*PAGE_SIZE) >> 10,
+#endif
+
+	       VMALLOC_START, VMALLOC_END,
+	       (VMALLOC_END - VMALLOC_START) >> 20,
+
+	       (unsigned long)__va(0), (unsigned long)high_memory,
+	       ((unsigned long)high_memory - (unsigned long)__va(0)) >> 20,
+
+	       (unsigned long)&__init_begin, (unsigned long)&__init_end,
+	       ((unsigned long)&__init_end - (unsigned long)&__init_begin) >> 10,
+
+	       (unsigned long)&_etext, (unsigned long)&_edata,
+	       ((unsigned long)&_edata - (unsigned long)&_etext) >> 10,
+
+	       (unsigned long)&_text, (unsigned long)&_etext,
+	       ((unsigned long)&_etext - (unsigned long)&_text) >> 10);
+
+#ifdef CONFIG_HIGHMEM
+	BUG_ON(PKMAP_BASE+LAST_PKMAP*PAGE_SIZE > FIXADDR_START);
+	BUG_ON(VMALLOC_END                     > PKMAP_BASE);
+#endif
+	BUG_ON(VMALLOC_START                   > VMALLOC_END);
+	BUG_ON((unsigned long)high_memory      > VMALLOC_START);
+#endif /* double-sanity-check paranoia */
+
+#ifdef CONFIG_X86_PAE
+	if (!cpu_has_pae)
+		panic("cannot execute a PAE-enabled kernel on a PAE-less CPU!");
+#endif
+	if (boot_cpu_data.wp_works_ok < 0)
+		test_wp_bit();
+
+	/*
+	 * Subtle. SMP is doing it's boot stuff late (because it has to
+	 * fork idle threads) - but it also needs low mappings for the
+	 * protected-mode entry to work. We zap these entries only after
+	 * the WP-bit has been tested.
+	 */
+#ifndef CONFIG_SMP
+	zap_low_mappings();
+#endif
+}
+
+#ifdef CONFIG_MEMORY_HOTPLUG
+int arch_add_memory(int nid, u64 start, u64 size)
+{
+	struct pglist_data *pgdata = NODE_DATA(nid);
+	struct zone *zone = pgdata->node_zones + ZONE_HIGHMEM;
+	unsigned long start_pfn = start >> PAGE_SHIFT;
+	unsigned long nr_pages = size >> PAGE_SHIFT;
+
+	return __add_pages(zone, start_pfn, nr_pages);
+}
+
+int remove_memory(u64 start, u64 size)
+{
+	return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(remove_memory);
+#endif
+
+struct kmem_cache *pmd_cache;
+
+void __init pgtable_cache_init(void)
+{
+	size_t pgd_size = PTRS_PER_PGD*sizeof(pgd_t);
+
+	if (PTRS_PER_PMD > 1) {
+		pmd_cache = kmem_cache_create("pmd",
+					PTRS_PER_PMD*sizeof(pmd_t),
+					PTRS_PER_PMD*sizeof(pmd_t),
+					SLAB_PANIC,
+					pmd_ctor);
+		if (!SHARED_KERNEL_PMD) {
+			/* If we're in PAE mode and have a non-shared
+			   kernel pmd, then the pgd size must be a
+			   page size.  This is because the pgd_list
+			   links through the page structure, so there
+			   can only be one pgd per page for this to
+			   work. */
+			pgd_size = PAGE_SIZE;
+		}
+	}
+}
+
+/*
+ * This function cannot be __init, since exceptions don't work in that
+ * section.  Put this after the callers, so that it cannot be inlined.
+ */
+static int noinline do_test_wp_bit(void)
+{
+	char tmp_reg;
+	int flag;
+
+	__asm__ __volatile__(
+		"	movb %0,%1	\n"
+		"1:	movb %1,%0	\n"
+		"	xorl %2,%2	\n"
+		"2:			\n"
+		".section __ex_table,\"a\"\n"
+		"	.align 4	\n"
+		"	.long 1b,2b	\n"
+		".previous		\n"
+		:"=m" (*(char *)fix_to_virt(FIX_WP_TEST)),
+		 "=q" (tmp_reg),
+		 "=r" (flag)
+		:"2" (1)
+		:"memory");
+	
+	return flag;
+}
+
+#ifdef CONFIG_DEBUG_RODATA
+
+void mark_rodata_ro(void)
+{
+	unsigned long start = PFN_ALIGN(_text);
+	unsigned long size = PFN_ALIGN(_etext) - start;
+
+#ifndef CONFIG_KPROBES
+#ifdef CONFIG_HOTPLUG_CPU
+	/* It must still be possible to apply SMP alternatives. */
+	if (num_possible_cpus() <= 1)
+#endif
+	{
+		change_page_attr(virt_to_page(start),
+		                 size >> PAGE_SHIFT, PAGE_KERNEL_RX);
+		printk("Write protecting the kernel text: %luk\n", size >> 10);
+	}
+#endif
+	start += size;
+	size = (unsigned long)__end_rodata - start;
+	change_page_attr(virt_to_page(start),
+	                 size >> PAGE_SHIFT, PAGE_KERNEL_RO);
+	printk("Write protecting the kernel read-only data: %luk\n",
+	       size >> 10);
+
+	/*
+	 * change_page_attr() requires a global_flush_tlb() call after it.
+	 * We do this after the printk so that if something went wrong in the
+	 * change, the printk gets out at least to give a better debug hint
+	 * of who is the culprit.
+	 */
+	global_flush_tlb();
+}
+#endif
+
+void free_init_pages(char *what, unsigned long begin, unsigned long end)
+{
+	unsigned long addr;
+
+	for (addr = begin; addr < end; addr += PAGE_SIZE) {
+		ClearPageReserved(virt_to_page(addr));
+		init_page_count(virt_to_page(addr));
+		memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
+		free_page(addr);
+		totalram_pages++;
+	}
+	printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);
+}
+
+void free_initmem(void)
+{
+	free_init_pages("unused kernel memory",
+			(unsigned long)(&__init_begin),
+			(unsigned long)(&__init_end));
+}
+
+#ifdef CONFIG_BLK_DEV_INITRD
+void free_initrd_mem(unsigned long start, unsigned long end)
+{
+	free_init_pages("initrd memory", start, end);
+}
+#endif
+