/*
* 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/memory_hotplug.h>
#include <linux/initrd.h>
#include <linux/cpumask.h>
#include <asm/asm.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/bugs.h>
#include <asm/tlb.h>
#include <asm/tlbflush.h>
#include <asm/pgalloc.h>
#include <asm/sections.h>
#include <asm/paravirt.h>
#include <asm/setup.h>
#include <asm/cacheflush.h>
unsigned int __VMALLOC_RESERVE = 128 << 20;
unsigned long max_pfn_mapped;
DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
unsigned long highstart_pfn, highend_pfn;
static noinline int 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(&init_mm, __pa(pmd_table) >> PAGE_SHIFT);
set_pgd(pgd, __pgd(__pa(pmd_table) | _PAGE_PRESENT));
pud = pud_offset(pgd, 0);
BUG_ON(pmd_table != pmd_offset(pud, 0));
}
#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 = NULL;
#ifdef CONFIG_DEBUG_PAGEALLOC
page_table = (pte_t *) alloc_bootmem_pages(PAGE_SIZE);
#endif
if (!page_table) {
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)
{
int pgd_idx, pmd_idx;
unsigned long vaddr;
pgd_t *pgd;
pmd_t *pmd;
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)
{
int pgd_idx, pmd_idx, pte_ofs;
unsigned long pfn;
pgd_t *pgd;
pmd_t *pmd;
pte_t *pte;
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 addr = pfn * PAGE_SIZE + PAGE_OFFSET;
/*
* Map with big pages if possible, otherwise
* create normal page tables:
*
* Don't use a large page for the first 2/4MB of memory
* because there are often fixed size MTRRs in there
* and overlapping MTRRs into large pages can cause
* slowdowns.
*/
if (cpu_has_pse && !(pgd_idx == 0 && pmd_idx == 0)) {
unsigned int addr2;
pgprot_t prot = PAGE_KERNEL_LARGE;
addr2 = (pfn + PTRS_PER_PTE-1) * PAGE_SIZE +
PAGE_OFFSET + PAGE_SIZE-1;
if (is_kernel_text(addr) ||
is_kernel_text(addr2))
prot = PAGE_KERNEL_LARGE_EXEC;
set_pmd(pmd, pfn_pmd(pfn, prot));
pfn += PTRS_PER_PTE;
max_pfn_mapped = pfn;
continue;
}
pte = one_page_table_init(pmd);
for (pte_ofs = 0;
pte_ofs < PTRS_PER_PTE && pfn < max_low_pfn;
pte++, pfn++, pte_ofs++, addr += PAGE_SIZE) {
pgprot_t prot = PAGE_KERNEL;
if (is_kernel_text(addr))
prot = PAGE_KERNEL_EXEC;
set_pte(pte, pfn_pte(pfn, prot));
}
max_pfn_mapped = pfn;
}
}
}
static inline int page_kills_ppro(unsigned long pagenr)
{
if (pagenr >= 0x70000 && pagenr <= 0x7003F)
return 1;
return 0;
}
#ifdef CONFIG_HIGHMEM
pte_t *kmap_pte;
pgprot_t kmap_prot;
static inline pte_t *kmap_get_fixmap_pte(unsigned long vaddr)
{
return 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)
{
unsigned long vaddr;
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
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));
}
#ifndef CONFIG_NUMA
static void __init set_highmem_pages_init(int bad_ppro)
{
int pfn;
for (pfn = highstart_pfn; pfn < highend_pfn; pfn++) {
/*
* Holes under sparsemem might not have no mem_map[]:
*/
if (pfn_valid(pfn))
add_one_highpage_init(pfn_to_page(pfn), pfn, bad_ppro);
}
totalram_pages += totalhigh_pages;
}
#endif /* !CONFIG_NUMA */
#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 */
pteval_t __PAGE_KERNEL = _PAGE_KERNEL;
EXPORT_SYMBOL(__PAGE_KERNEL);
pteval_t __PAGE_KERNEL_EXEC = _PAGE_KERNEL_EXEC;
void __init native_pagetable_setup_start(pgd_t *base)
{
unsigned long pfn, va;
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
/*
* Remove any mappings which extend past the end of physical
* memory from the boot time page table:
*/
for (pfn = max_low_pfn + 1; pfn < 1<<(32-PAGE_SHIFT); pfn++) {
va = PAGE_OFFSET + (pfn<<PAGE_SHIFT);
pgd = base + pgd_index(va);
if (!pgd_present(*pgd))
break;
pud = pud_offset(pgd, va);
pmd = pmd_offset(pud, va);
if (!pmd_present(*pmd))
break;
pte = pte_offset_kernel(pmd, va);
if (!pte_present(*pte))
break;
pte_clear(NULL, va, pte);
}
paravirt_alloc_pd(&init_mm, __pa(base) >> PAGE_SHIFT);
}
void __init native_pagetable_setup_done(pgd_t *base)
{
}
/*
* 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/x86/kernel/head_32.S. 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)
{
pgd_t *pgd_base = swapper_pg_dir;
unsigned long vaddr, end;
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():
*/
early_ioremap_clear();
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);
early_ioremap_reset();
permanent_kmaps_init(pgd_base);
paravirt_pagetable_setup_done(pgd_base);
}
#ifdef CONFIG_ACPI_SLEEP
/*
* ACPI suspend needs this for resume, because things like the intel-agp
* driver might have split up a kernel 4MB mapping.
*/
char 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 /* !CONFIG_ACPI_SLEEP */
static inline void save_pg_dir(void)
{
}
#endif /* !CONFIG_ACPI_SLEEP */
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;
pteval_t __supported_pte_mask __read_mostly = ~_PAGE_NX;
EXPORT_SYMBOL_GPL(__supported_pte_mask);
#ifdef CONFIG_X86_PAE
static int disable_nx __initdata;
/*
* 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;
}
}
}
#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(KERN_INFO "NX (Execute Disable) protection: active\n");
#endif
pagetable_init();
load_cr3(swapper_pg_dir);
__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(KERN_INFO
"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(KERN_CONT "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(KERN_CONT "Ok.\n");
}
}
static struct kcore_list kcore_mem, kcore_vmalloc;
void __init mem_init(void)
{
int codesize, reservedpages, datasize, initsize;
int tmp, 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(KERN_INFO "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 */
if (boot_cpu_data.wp_works_ok < 0)
test_wp_bit();
cpa_init();
/*
* 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);
}
#endif
/*
* 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 noinline int 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"
_ASM_EXTABLE(1b,2b)
:"=m" (*(char *)fix_to_virt(FIX_WP_TEST)),
"=q" (tmp_reg),
"=r" (flag)
:"2" (1)
:"memory");
return flag;
}
#ifdef CONFIG_DEBUG_RODATA
const int rodata_test_data = 0xC3;
EXPORT_SYMBOL_GPL(rodata_test_data);
void mark_rodata_ro(void)
{
unsigned long start = PFN_ALIGN(_text);
unsigned long size = PFN_ALIGN(_etext) - start;
set_pages_ro(virt_to_page(start), size >> PAGE_SHIFT);
printk(KERN_INFO "Write protecting the kernel text: %luk\n",
size >> 10);
#ifdef CONFIG_CPA_DEBUG
printk(KERN_INFO "Testing CPA: Reverting %lx-%lx\n",
start, start+size);
set_pages_rw(virt_to_page(start), size>>PAGE_SHIFT);
printk(KERN_INFO "Testing CPA: write protecting again\n");
set_pages_ro(virt_to_page(start), size>>PAGE_SHIFT);
#endif
start += size;
size = (unsigned long)__end_rodata - start;
set_pages_ro(virt_to_page(start), size >> PAGE_SHIFT);
printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
size >> 10);
rodata_test();
#ifdef CONFIG_CPA_DEBUG
printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, start + size);
set_pages_rw(virt_to_page(start), size >> PAGE_SHIFT);
printk(KERN_INFO "Testing CPA: write protecting again\n");
set_pages_ro(virt_to_page(start), size >> PAGE_SHIFT);
#endif
}
#endif
void free_init_pages(char *what, unsigned long begin, unsigned long end)
{
#ifdef CONFIG_DEBUG_PAGEALLOC
/*
* If debugging page accesses then do not free this memory but
* mark them not present - any buggy init-section access will
* create a kernel page fault:
*/
printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n",
begin, PAGE_ALIGN(end));
set_memory_np(begin, (end - begin) >> PAGE_SHIFT);
#else
unsigned long addr;
/*
* We just marked the kernel text read only above, now that
* we are going to free part of that, we need to make that
* writeable first.
*/
set_memory_rw(begin, (end - begin) >> PAGE_SHIFT);
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);
#endif
}
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
