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|
// SPDX-License-Identifier: GPL-2.0-only
/*
* 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 <linux/bootmem_info.h>
#include <asm/processor.h>
#include <asm/bios_ebda.h>
#include <linux/uaccess.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 <asm/ftrace.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);
}
}
static void sync_global_pgds_l4(unsigned long start, unsigned long end)
{
unsigned long addr;
for (addr = start; addr <= end; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
pgd_t *pgd_ref = pgd_offset_k(addr);
const p4d_t *p4d_ref;
struct page *page;
/*
* With folded p4d, pgd_none() is always false, we need to
* handle synchronization on p4d level.
*/
MAYBE_BUILD_BUG_ON(pgd_none(*pgd_ref));
p4d_ref = p4d_offset(pgd_ref, addr);
if (p4d_none(*p4d_ref))
continue;
spin_lock(&pgd_lock);
list_for_each_entry(page, &pgd_list, lru) {
pgd_t *pgd;
p4d_t *p4d;
spinlock_t *pgt_lock;
pgd = (pgd_t *)page_address(page) + pgd_index(addr);
p4d = p4d_offset(pgd, addr);
/* the pgt_lock only for Xen */
pgt_lock = &pgd_page_get_mm(page)->page_table_lock;
spin_lock(pgt_lock);
if (!p4d_none(*p4d_ref) && !p4d_none(*p4d))
BUG_ON(p4d_pgtable(*p4d)
!= p4d_pgtable(*p4d_ref));
if (p4d_none(*p4d))
set_p4d(p4d, *p4d_ref);
spin_unlock(pgt_lock);
}
spin_unlock(&pgd_lock);
}
}
/*
* When memory was added make sure all the processes MM have
* suitable PGD entries in the local PGD level page.
*/
static void sync_global_pgds(unsigned long start, unsigned long end)
{
if (pgtable_l5_enabled())
sync_global_pgds_l5(start, end);
else
sync_global_pgds_l4(start, end);
}
/*
* NOTE: This function is marked __ref because it calls __init function
* (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0.
*/
static __ref void *spp_getpage(void)
{
void *ptr;
if (after_bootmem)
ptr = (void *) get_zeroed_page(GFP_ATOMIC);
else
ptr = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
panic("set_pte_phys: cannot allocate page data %s\n",
after_bootmem ? "after bootmem" : "");
}
pr_debug("spp_getpage %p\n", ptr);
return ptr;
}
static p4d_t *fill_p4d(pgd_t *pgd, unsigned long vaddr)
{
if (pgd_none(*pgd)) {
p4d_t *p4d = (p4d_t *)spp_getpage();
pgd_populate(&init_mm, pgd, p4d);
if (p4d != p4d_offset(pgd, 0))
printk(KERN_ERR "PAGETABLE BUG #00! %p <-> %p\n",
p4d, p4d_offset(pgd, 0));
}
return p4d_offset(pgd, vaddr);
}
static pud_t *fill_pud(p4d_t *p4d, unsigned long vaddr)
{
if (p4d_none(*p4d)) {
pud_t *pud = (pud_t *)spp_getpage();
p4d_populate(&init_mm, p4d, pud);
if (pud != pud_offset(p4d, 0))
printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
pud, pud_offset(p4d, 0));
}
return pud_offset(p4d, vaddr);
}
static pmd_t *fill_pmd(pud_t *pud, unsigned long vaddr)
{
if (pud_none(*pud)) {
pmd_t *pmd = (pmd_t *) spp_getpage();
pud_populate(&init_mm, pud, pmd);
if (pmd != pmd_offset(pud, 0))
printk(KERN_ERR "PAGETABLE BUG #02! %p <-> %p\n",
pmd, pmd_offset(pud, 0));
}
return pmd_offset(pud, vaddr);
}
static pte_t *fill_pte(pmd_t *pmd, unsigned long vaddr)
{
if (pmd_none(*pmd)) {
pte_t *pte = (pte_t *) spp_getpage();
pmd_populate_kernel(&init_mm, pmd, pte);
if (pte != pte_offset_kernel(pmd, 0))
printk(KERN_ERR "PAGETABLE BUG #03!\n");
}
return pte_offset_kernel(pmd, vaddr);
}
static void __set_pte_vaddr(pud_t *pud, unsigned long vaddr, pte_t new_pte)
{
pmd_t *pmd = fill_pmd(pud, vaddr);
pte_t *pte = fill_pte(pmd, vaddr);
set_pte(pte, new_pte);
/*
* It's enough to flush this one mapping.
* (PGE mappings get flushed as well)
*/
flush_tlb_one_kernel(vaddr);
}
void set_pte_vaddr_p4d(p4d_t *p4d_page, unsigned long vaddr, pte_t new_pte)
{
p4d_t *p4d = p4d_page + p4d_index(vaddr);
pud_t *pud = fill_pud(p4d, vaddr);
__set_pte_vaddr(pud, vaddr, new_pte);
}
void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
{
pud_t *pud = pud_page + pud_index(vaddr);
__set_pte_vaddr(pud, vaddr, new_pte);
}
void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
{
pgd_t *pgd;
p4d_t *p4d_page;
pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval));
pgd = pgd_offset_k(vaddr);
if (pgd_none(*pgd)) {
printk(KERN_ERR
"PGD FIXMAP MISSING, it should be setup in head.S!\n");
return;
}
p4d_page = p4d_offset(pgd, 0);
set_pte_vaddr_p4d(p4d_page, vaddr, pteval);
}
pmd_t * __init populate_extra_pmd(unsigned long vaddr)
{
pgd_t *pgd;
p4d_t *p4d;
pud_t *pud;
pgd = pgd_offset_k(vaddr);
p4d = fill_p4d(pgd, vaddr);
pud = fill_pud(p4d, vaddr);
return fill_pmd(pud, vaddr);
}
pte_t * __init populate_extra_pte(unsigned long vaddr)
{
pmd_t *pmd;
pmd = populate_extra_pmd(vaddr);
return fill_pte(pmd, vaddr);
}
/*
* Create large page table mappings for a range of physical addresses.
*/
static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
enum page_cache_mode cache)
{
pgd_t *pgd;
p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;
pgprot_t prot;
pgprot_val(prot) = pgprot_val(PAGE_KERNEL_LARGE) |
protval_4k_2_large(cachemode2protval(cache));
BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK));
for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
pgd = pgd_offset_k((unsigned long)__va(phys));
if (pgd_none(*pgd)) {
p4d = (p4d_t *) spp_getpage();
set_pgd(pgd, __pgd(__pa(p4d) | _KERNPG_TABLE |
_PAGE_USER));
}
p4d = p4d_offset(pgd, (unsigned long)__va(phys));
if (p4d_none(*p4d)) {
pud = (pud_t *) spp_getpage();
set_p4d(p4d, __p4d(__pa(pud) | _KERNPG_TABLE |
_PAGE_USER));
}
pud = pud_offset(p4d, (unsigned long)__va(phys));
if (pud_none(*pud)) {
pmd = (pmd_t *) spp_getpage();
set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
_PAGE_USER));
}
pmd = pmd_offset(pud, phys);
BUG_ON(!pmd_none(*pmd));
set_pmd(pmd, __pmd(phys | pgprot_val(prot)));
}
}
void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
{
__init_extra_mapping(phys, size, _PAGE_CACHE_MODE_WB);
}
void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
{
__init_extra_mapping(phys, size, _PAGE_CACHE_MODE_UC);
}
/*
* The head.S code sets up the kernel high mapping:
*
* from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
*
* phys_base holds the negative offset to the kernel, which is added
* to the compile time generated pmds. This results in invalid pmds up
* to the point where we hit the physaddr 0 mapping.
*
* We limit the mappings to the region from _text to _brk_end. _brk_end
* is rounded up to the 2MB boundary. This catches the invalid pmds as
* well, as they are located before _text:
*/
void __init cleanup_highmap(void)
{
unsigned long vaddr = __START_KERNEL_map;
unsigned long vaddr_end = __START_KERNEL_map + KERNEL_IMAGE_SIZE;
unsigned long end = roundup((unsigned long)_brk_end, PMD_SIZE) - 1;
pmd_t *pmd = level2_kernel_pgt;
/*
* Native path, max_pfn_mapped is not set yet.
* Xen has valid max_pfn_mapped set in
* arch/x86/xen/mmu.c:xen_setup_kernel_pagetable().
*/
if (max_pfn_mapped)
vaddr_end = __START_KERNEL_map + (max_pfn_mapped << PAGE_SHIFT);
for (; vaddr + PMD_SIZE - 1 < vaddr_end; pmd++, vaddr += PMD_SIZE) {
if (pmd_none(*pmd))
continue;
if (vaddr < (unsigned long) _text || vaddr > end)
set_pmd(pmd, __pmd(0));
}
}
/*
* Create PTE level page table mapping for physical addresses.
* It returns the last physical address mapped.
*/
static unsigned long __meminit
phys_pte_init(pte_t *pte_page, unsigned long paddr, unsigned long paddr_end,
pgprot_t prot, bool init)
{
unsigned long pages = 0, paddr_next;
unsigned long paddr_last = paddr_end;
pte_t *pte;
int i;
pte = pte_page + pte_index(paddr);
i = pte_index(paddr);
for (; i < PTRS_PER_PTE; i++, paddr = paddr_next, pte++) {
paddr_next = (paddr & PAGE_MASK) + PAGE_SIZE;
if (paddr >= paddr_end) {
if (!after_bootmem &&
!e820__mapped_any(paddr & PAGE_MASK, paddr_next,
E820_TYPE_RAM) &&
!e820__mapped_any(paddr & PAGE_MASK, paddr_next,
E820_TYPE_RESERVED_KERN))
set_pte_init(pte, __pte(0), init);
continue;
}
/*
* We will re-use the existing mapping.
* Xen for example has some special requirements, like mapping
* pagetable pages as RO. So assume someone who pre-setup
* these mappings are more intelligent.
*/
if (!pte_none(*pte)) {
if (!after_bootmem)
pages++;
continue;
}
if (0)
pr_info(" pte=%p addr=%lx pte=%016lx\n", pte, paddr,
pfn_pte(paddr >> PAGE_SHIFT, PAGE_KERNEL).pte);
pages++;
set_pte_init(pte, pfn_pte(paddr >> PAGE_SHIFT, prot), init);
paddr_last = (paddr & PAGE_MASK) + PAGE_SIZE;
}
update_page_count(PG_LEVEL_4K, pages);
return paddr_last;
}
/*
* Create PMD level page table mapping for physical addresses. The virtual
* and physical address have to be aligned at this level.
* It returns the last physical address mapped.
*/
static unsigned long __meminit
phys_pmd_init(pmd_t *pmd_page, unsigned long paddr, unsigned long paddr_end,
unsigned long page_size_mask, pgprot_t prot, bool init)
{
unsigned long pages = 0, paddr_next;
unsigned long paddr_last = paddr_end;
int i = pmd_index(paddr);
for (; i < PTRS_PER_PMD; i++, paddr = paddr_next) {
pmd_t *pmd = pmd_page + pmd_index(paddr);
pte_t *pte;
pgprot_t new_prot = prot;
paddr_next = (paddr & PMD_MASK) + PMD_SIZE;
if (paddr >= paddr_end) {
if (!after_bootmem &&
!e820__mapped_any(paddr & PMD_MASK, paddr_next,
E820_TYPE_RAM) &&
!e820__mapped_any(paddr & PMD_MASK, paddr_next,
E820_TYPE_RESERVED_KERN))
set_pmd_init(pmd, __pmd(0), init);
continue;
}
if (!pmd_none(*pmd)) {
if (!pmd_large(*pmd)) {
spin_lock(&init_mm.page_table_lock);
pte = (pte_t *)pmd_page_vaddr(*pmd);
paddr_last = phys_pte_init(pte, paddr,
paddr_end, prot,
init);
spin_unlock(&init_mm.page_table_lock);
continue;
}
/*
* If we are ok with PG_LEVEL_2M mapping, then we will
* use the existing mapping,
*
* Otherwise, we will split the large page mapping but
* use the same existing protection bits except for
* large page, so that we don't violate Intel's TLB
* Application note (317080) which says, while changing
* the page sizes, new and old translations should
* not differ with respect to page frame and
* attributes.
*/
if (page_size_mask & (1 << PG_LEVEL_2M)) {
if (!after_bootmem)
pages++;
paddr_last = paddr_next;
continue;
}
new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd));
}
if (page_size_mask & (1<<PG_LEVEL_2M)) {
pages++;
spin_lock(&init_mm.page_table_lock);
set_pte_init((pte_t *)pmd,
pfn_pte((paddr & PMD_MASK) >> PAGE_SHIFT,
__pgprot(pgprot_val(prot) | _PAGE_PSE)),
init);
spin_unlock(&init_mm.page_table_lock);
paddr_last = paddr_next;
continue;
}
pte = alloc_low_page();
paddr_last = phys_pte_init(pte, paddr, paddr_end, new_prot, init);
spin_lock(&init_mm.page_table_lock);
pmd_populate_kernel_init(&init_mm, pmd, pte, init);
spin_unlock(&init_mm.page_table_lock);
}
update_page_count(PG_LEVEL_2M, pages);
return paddr_last;
}
/*
* Create PUD level page table mapping for physical addresses. The virtual
* and physical address do not have to be aligned at this level. KASLR can
* randomize virtual addresses up to this level.
* It returns the last physical address mapped.
*/
static unsigned long __meminit
phys_pud_init(pud_t *pud_page, unsigned long paddr, unsigned long paddr_end,
unsigned long page_size_mask, pgprot_t _prot, bool init)
{
unsigned long pages = 0, paddr_next;
unsigned long paddr_last = paddr_end;
unsigned long vaddr = (unsigned long)__va(paddr);
int i = pud_index(vaddr);
for (; i < PTRS_PER_PUD; i++, paddr = paddr_next) {
pud_t *pud;
pmd_t *pmd;
pgprot_t prot = _prot;
vaddr = (unsigned long)__va(paddr);
pud = pud_page + pud_index(vaddr);
paddr_next = (paddr & PUD_MASK) + PUD_SIZE;
if (paddr >= paddr_end) {
if (!after_bootmem &&
!e820__mapped_any(paddr & PUD_MASK, paddr_next,
E820_TYPE_RAM) &&
!e820__mapped_any(paddr & PUD_MASK, paddr_next,
E820_TYPE_RESERVED_KERN))
set_pud_init(pud, __pud(0), init);
continue;
}
if (!pud_none(*pud)) {
if (!pud_large(*pud)) {
pmd = pmd_offset(pud, 0);
paddr_last = phys_pmd_init(pmd, paddr,
paddr_end,
page_size_mask,
prot, init);
continue;
}
/*
* If we are ok with PG_LEVEL_1G mapping, then we will
* use the existing mapping.
*
* Otherwise, we will split the gbpage mapping but use
* the same existing protection bits except for large
* page, so that we don't violate Intel's TLB
* Application note (317080) which says, while changing
* the page sizes, new and old translations should
* not differ with respect to page frame and
* attributes.
*/
if (page_size_mask & (1 << PG_LEVEL_1G)) {
if (!after_bootmem)
pages++;
paddr_last = paddr_next;
continue;
}
prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud));
}
if (page_size_mask & (1<<PG_LEVEL_1G)) {
pages++;
spin_lock(&init_mm.page_table_lock);
prot = __pgprot(pgprot_val(prot) | _PAGE_PSE);
set_pte_init((pte_t *)pud,
pfn_pte((paddr & PUD_MASK) >> PAGE_SHIFT,
prot),
init);
spin_unlock(&init_mm.page_table_lock);
paddr_last = paddr_next;
continue;
}
pmd = alloc_low_page();
paddr_last = phys_pmd_init(pmd, paddr, paddr_end,
page_size_mask, prot, init);
spin_lock(&init_mm.page_table_lock);
pud_populate_init(&init_mm, pud, pmd, init);
spin_unlock(&init_mm.page_table_lock);
}
update_page_count(PG_LEVEL_1G, pages);
return paddr_last;
}
static unsigned long __meminit
phys_p4d_init(p4d_t *p4d_page, unsigned long paddr, unsigned long paddr_end,
unsigned long page_size_mask, pgprot_t prot, bool init)
{
unsigned long vaddr, vaddr_end, vaddr_next, paddr_next, paddr_last;
paddr_last = paddr_end;
vaddr = (unsigned long)__va(paddr);
vaddr_end = (unsigned long)__va(paddr_end);
if (!pgtable_l5_enabled())
return phys_pud_init((pud_t *) p4d_page, paddr, paddr_end,
page_size_mask, prot, init);
for (; vaddr < vaddr_end; vaddr = vaddr_next) {
p4d_t *p4d = p4d_page + p4d_index(vaddr);
pud_t *pud;
vaddr_next = (vaddr & P4D_MASK) + P4D_SIZE;
paddr = __pa(vaddr);
if (paddr >= paddr_end) {
paddr_next = __pa(vaddr_next);
if (!after_bootmem &&
!e820__mapped_any(paddr & P4D_MASK, paddr_next,
E820_TYPE_RAM) &&
!e820__mapped_any(paddr & P4D_MASK, paddr_next,
E820_TYPE_RESERVED_KERN))
set_p4d_init(p4d, __p4d(0), init);
continue;
}
if (!p4d_none(*p4d)) {
pud = pud_offset(p4d, 0);
paddr_last = phys_pud_init(pud, paddr, __pa(vaddr_end),
page_size_mask, prot, init);
continue;
}
pud = alloc_low_page();
paddr_last = phys_pud_init(pud, paddr, __pa(vaddr_end),
page_size_mask, prot, init);
spin_lock(&init_mm.page_table_lock);
p4d_populate_init(&init_mm, p4d, pud, init);
spin_unlock(&init_mm.page_table_lock);
}
return paddr_last;
}
static unsigned long __meminit
__kernel_physical_mapping_init(unsigned long paddr_start,
unsigned long paddr_end,
unsigned long page_size_mask,
pgprot_t prot, bool init)
{
bool pgd_changed = false;
unsigned long vaddr, vaddr_start, vaddr_end, vaddr_next, paddr_last;
paddr_last = paddr_end;
vaddr = (unsigned long)__va(paddr_start);
vaddr_end = (unsigned long)__va(paddr_end);
vaddr_start = vaddr;
for (; vaddr < vaddr_end; vaddr = vaddr_next) {
pgd_t *pgd = pgd_offset_k(vaddr);
p4d_t *p4d;
vaddr_next = (vaddr & PGDIR_MASK) + PGDIR_SIZE;
if (pgd_val(*pgd)) {
p4d = (p4d_t *)pgd_page_vaddr(*pgd);
paddr_last = phys_p4d_init(p4d, __pa(vaddr),
__pa(vaddr_end),
page_size_mask,
prot, init);
continue;
}
p4d = alloc_low_page();
paddr_last = phys_p4d_init(p4d, __pa(vaddr), __pa(vaddr_end),
page_size_mask, prot, init);
spin_lock(&init_mm.page_table_lock);
if (pgtable_l5_enabled())
pgd_populate_init(&init_mm, pgd, p4d, init);
else
p4d_populate_init(&init_mm, p4d_offset(pgd, vaddr),
(pud_t *) p4d, init);
spin_unlock(&init_mm.page_table_lock);
pgd_changed = true;
}
if (pgd_changed)
sync_global_pgds(vaddr_start, vaddr_end - 1);
return paddr_last;
}
/*
* Create page table mapping for the physical memory for specific physical
* addresses. Note that it can only be used to populate non-present entries.
* The virtual and physical addresses have to be aligned on PMD level
* down. It returns the last physical address mapped.
*/
unsigned long __meminit
kernel_physical_mapping_init(unsigned long paddr_start,
unsigned long paddr_end,
unsigned long page_size_mask, pgprot_t prot)
{
return __kernel_physical_mapping_init(paddr_start, paddr_end,
page_size_mask, prot, true);
}
/*
* This function is similar to kernel_physical_mapping_init() above with the
* exception that it uses set_{pud,pmd}() instead of the set_{pud,pte}_safe()
* when updating the mapping. The caller is responsible to flush the TLBs after
* the function returns.
*/
unsigned long __meminit
kernel_physical_mapping_change(unsigned long paddr_start,
unsigned long paddr_end,
unsigned long page_size_mask)
{
return __kernel_physical_mapping_init(paddr_start, paddr_end,
page_size_mask, PAGE_KERNEL,
false);
}
#ifndef CONFIG_NUMA
void __init initmem_init(void)
{
memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0);
}
#endif
void __init paging_init(void)
{
sparse_init();
/*
* clear the default setting with node 0
* note: don't use nodes_clear here, that is really clearing when
* numa support is not compiled in, and later node_set_state
* will not set it back.
*/
node_clear_state(0, N_MEMORY);
node_clear_state(0, N_NORMAL_MEMORY);
zone_sizes_init();
}
#ifdef CONFIG_SPARSEMEM_VMEMMAP
#define PAGE_UNUSED 0xFD
/*
* The unused vmemmap range, which was not yet memset(PAGE_UNUSED), ranges
* from unused_pmd_start to next PMD_SIZE boundary.
*/
static unsigned long unused_pmd_start __meminitdata;
static void __meminit vmemmap_flush_unused_pmd(void)
{
if (!unused_pmd_start)
return;
/*
* Clears (unused_pmd_start, PMD_END]
*/
memset((void *)unused_pmd_start, PAGE_UNUSED,
ALIGN(unused_pmd_start, PMD_SIZE) - unused_pmd_start);
unused_pmd_start = 0;
}
#ifdef CONFIG_MEMORY_HOTPLUG
/* Returns true if the PMD is completely unused and thus it can be freed */
static bool __meminit vmemmap_pmd_is_unused(unsigned long addr, unsigned long end)
{
unsigned long start = ALIGN_DOWN(addr, PMD_SIZE);
/*
* Flush the unused range cache to ensure that memchr_inv() will work
* for the whole range.
*/
vmemmap_flush_unused_pmd();
memset((void *)addr, PAGE_UNUSED, end - addr);
return !memchr_inv((void *)start, PAGE_UNUSED, PMD_SIZE);
}
#endif
static void __meminit __vmemmap_use_sub_pmd(unsigned long start)
{
/*
* As we expect to add in the same granularity as we remove, it's
* sufficient to mark only some piece used to block the memmap page from
* getting removed when removing some other adjacent memmap (just in
* case the first memmap never gets initialized e.g., because the memory
* block never gets onlined).
*/
memset((void *)start, 0, sizeof(struct page));
}
static void __meminit vmemmap_use_sub_pmd(unsigned long start, unsigned long end)
{
/*
* We only optimize if the new used range directly follows the
* previously unused range (esp., when populating consecutive sections).
*/
if (unused_pmd_start == start) {
if (likely(IS_ALIGNED(end, PMD_SIZE)))
unused_pmd_start = 0;
else
unused_pmd_start = end;
return;
}
/*
* If the range does not contiguously follows previous one, make sure
* to mark the unused range of the previous one so it can be removed.
*/
vmemmap_flush_unused_pmd();
__vmemmap_use_sub_pmd(start);
}
static void __meminit vmemmap_use_new_sub_pmd(unsigned long start, unsigned long end)
{
const unsigned long page = ALIGN_DOWN(start, PMD_SIZE);
vmemmap_flush_unused_pmd();
/*
* Could be our memmap page is filled with PAGE_UNUSED already from a
* previous remove. Make sure to reset it.
*/
__vmemmap_use_sub_pmd(start);
/*
* Mark with PAGE_UNUSED the unused parts of the new memmap range
*/
if (!IS_ALIGNED(start, PMD_SIZE))
memset((void *)page, PAGE_UNUSED, start - page);
/*
* We want to avoid memset(PAGE_UNUSED) when populating the vmemmap of
* consecutive sections. Remember for the last added PMD where the
* unused range begins.
*/
if (!IS_ALIGNED(end, PMD_SIZE))
unused_pmd_start = end;
}
#endif
/*
* Memory hotplug specific functions
*/
#ifdef CONFIG_MEMORY_HOTPLUG
/*
* After memory hotplug the variables max_pfn, max_low_pfn and high_memory need
* updating.
*/
static void update_end_of_memory_vars(u64 start, u64 size)
{
unsigned long end_pfn = PFN_UP(start + size);
if (end_pfn > max_pfn) {
max_pfn = end_pfn;
max_low_pfn = end_pfn;
high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
}
}
int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
struct mhp_params *params)
{
int ret;
ret = __add_pages(nid, start_pfn, nr_pages, params);
WARN_ON_ONCE(ret);
/* update max_pfn, max_low_pfn and high_memory */
update_end_of_memory_vars(start_pfn << PAGE_SHIFT,
nr_pages << PAGE_SHIFT);
return ret;
}
int arch_add_memory(int nid, u64 start, u64 size,
struct mhp_params *params)
{
unsigned long start_pfn = start >> PAGE_SHIFT;
unsigned long nr_pages = size >> PAGE_SHIFT;
init_memory_mapping(start, start + size, params->pgprot);
return add_pages(nid, start_pfn, nr_pages, params);
}
static void __meminit free_pagetable(struct page *page, int order)
{
unsigned long magic;
unsigned int nr_pages = 1 << order;
/* bootmem page has reserved flag */
if (PageReserved(page)) {
__ClearPageReserved(page);
magic = (unsigned long)page->freelist;
if (magic == SECTION_INFO || magic == MIX_SECTION_INFO) {
while (nr_pages--)
put_page_bootmem(page++);
} else
while (nr_pages--)
free_reserved_page(page++);
} else
free_pages((unsigned long)page_address(page), order);
}
static void __meminit free_hugepage_table(struct page *page,
struct vmem_altmap *altmap)
{
if (altmap)
vmem_altmap_free(altmap, PMD_SIZE / PAGE_SIZE);
else
free_pagetable(page, get_order(PMD_SIZE));
}
static void __meminit free_pte_table(pte_t *pte_start, pmd_t *pmd)
{
pte_t *pte;
int i;
for (i = 0; i < PTRS_PER_PTE; i++) {
pte = pte_start + i;
if (!pte_none(*pte))
return;
}
/* free a pte talbe */
free_pagetable(pmd_page(*pmd), 0);
spin_lock(&init_mm.page_table_lock);
pmd_clear(pmd);
spin_unlock(&init_mm.page_table_lock);
}
static void __meminit free_pmd_table(pmd_t *pmd_start, pud_t *pud)
{
pmd_t *pmd;
int i;
for (i = 0; i < PTRS_PER_PMD; i++) {
pmd = pmd_start + i;
if (!pmd_none(*pmd))
return;
}
/* free a pmd talbe */
free_pagetable(pud_page(*pud), 0);
spin_lock(&init_mm.page_table_lock);
pud_clear(pud);
spin_unlock(&init_mm.page_table_lock);
}
static void __meminit free_pud_table(pud_t *pud_start, p4d_t *p4d)
{
pud_t *pud;
int i;
for (i = 0; i < PTRS_PER_PUD; i++) {
pud = pud_start + i;
if (!pud_none(*pud))
return;
}
/* free a pud talbe */
free_pagetable(p4d_page(*p4d), 0);
spin_lock(&init_mm.page_table_lock);
p4d_clear(p4d);
spin_unlock(&init_mm.page_table_lock);
}
static void __meminit
remove_pte_table(pte_t *pte_start, unsigned long addr, unsigned long end,
bool direct)
{
unsigned long next, pages = 0;
pte_t *pte;
phys_addr_t phys_addr;
pte = pte_start + pte_index(addr);
for (; addr < end; addr = next, pte++) {
next = (addr + PAGE_SIZE) & PAGE_MASK;
if (next > end)
next = end;
if (!pte_present(*pte))
continue;
/*
* We mapped [0,1G) memory as identity mapping when
* initializing, in arch/x86/kernel/head_64.S. These
* pagetables cannot be removed.
*/
phys_addr = pte_val(*pte) + (addr & PAGE_MASK);
if (phys_addr < (phys_addr_t)0x40000000)
return;
if (!direct)
free_pagetable(pte_page(*pte), 0);
spin_lock(&init_mm.page_table_lock);
pte_clear(&init_mm, addr, pte);
spin_unlock(&init_mm.page_table_lock);
/* For non-direct mapping, pages means nothing. */
pages++;
}
/* Call free_pte_table() in remove_pmd_table(). */
flush_tlb_all();
if (direct)
update_page_count(PG_LEVEL_4K, -pages);
}
static void __meminit
remove_pmd_table(pmd_t *pmd_start, unsigned long addr, unsigned long end,
bool direct, struct vmem_altmap *altmap)
{
unsigned long next, pages = 0;
pte_t *pte_base;
pmd_t *pmd;
pmd = pmd_start + pmd_index(addr);
for (; addr < end; addr = next, pmd++) {
next = pmd_addr_end(addr, end);
if (!pmd_present(*pmd))
continue;
if (pmd_large(*pmd)) {
if (IS_ALIGNED(addr, PMD_SIZE) &&
IS_ALIGNED(next, PMD_SIZE)) {
if (!direct)
free_hugepage_table(pmd_page(*pmd),
altmap);
spin_lock(&init_mm.page_table_lock);
pmd_clear(pmd);
spin_unlock(&init_mm.page_table_lock);
pages++;
}
#ifdef CONFIG_SPARSEMEM_VMEMMAP
else if (vmemmap_pmd_is_unused(addr, next)) {
free_hugepage_table(pmd_page(*pmd),
altmap);
spin_lock(&init_mm.page_table_lock);
pmd_clear(pmd);
spin_unlock(&init_mm.page_table_lock);
}
#endif
continue;
}
pte_base = (pte_t *)pmd_page_vaddr(*pmd);
remove_pte_table(pte_base, addr, next, direct);
free_pte_table(pte_base, pmd);
}
/* Call free_pmd_table() in remove_pud_table(). */
if (direct)
update_page_count(PG_LEVEL_2M, -pages);
}
static void __meminit
remove_pud_table(pud_t *pud_start, unsigned long addr, unsigned long end,
struct vmem_altmap *altmap, bool direct)
{
unsigned long next, pages = 0;
pmd_t *pmd_base;
pud_t *pud;
pud = pud_start + pud_index(addr);
for (; addr < end; addr = next, pud++) {
next = pud_addr_end(addr, end);
if (!pud_present(*pud))
continue;
if (pud_large(*pud) &&
IS_ALIGNED(addr, PUD_SIZE) &&
IS_ALIGNED(next, PUD_SIZE)) {
spin_lock(&init_mm.page_table_lock);
pud_clear(pud);
spin_unlock(&init_mm.page_table_lock);
pages++;
continue;
}
pmd_base = pmd_offset(pud, 0);
remove_pmd_table(pmd_base, addr, next, direct, altmap);
free_pmd_table(pmd_base, pud);
}
if (direct)
update_page_count(PG_LEVEL_1G, -pages);
}
static void __meminit
remove_p4d_table(p4d_t *p4d_start, unsigned long addr, unsigned long end,
struct vmem_altmap *altmap, bool direct)
{
unsigned long next, pages = 0;
pud_t *pud_base;
p4d_t *p4d;
p4d = p4d_start + p4d_index(addr);
for (; addr < end; addr = next, p4d++) {
next = p4d_addr_end(addr, end);
if (!p4d_present(*p4d))
continue;
BUILD_BUG_ON(p4d_large(*p4d));
pud_base = pud_offset(p4d, 0);
remove_pud_table(pud_base, addr, next, altmap, direct);
/*
* For 4-level page tables we do not want to free PUDs, but in the
* 5-level case we should free them. This code will have to change
* to adapt for boot-time switching between 4 and 5 level page tables.
*/
if (pgtable_l5_enabled())
free_pud_table(pud_base, p4d);
}
if (direct)
update_page_count(PG_LEVEL_512G, -pages);
}
/* start and end are both virtual address. */
static void __meminit
remove_pagetable(unsigned long start, unsigned long end, bool direct,
struct vmem_altmap *altmap)
{
unsigned long next;
unsigned long addr;
pgd_t *pgd;
p4d_t *p4d;
for (addr = start; addr < end; addr = next) {
next = pgd_addr_end(addr, end);
pgd = pgd_offset_k(addr);
if (!pgd_present(*pgd))
continue;
p4d = p4d_offset(pgd, 0);
remove_p4d_table(p4d, addr, next, altmap, direct);
}
flush_tlb_all();
}
void __ref vmemmap_free(unsigned long start, unsigned long end,
struct vmem_altmap *altmap)
{
VM_BUG_ON(!IS_ALIGNED(start, PAGE_SIZE));
VM_BUG_ON(!IS_ALIGNED(end, PAGE_SIZE));
remove_pagetable(start, end, false, altmap);
}
static void __meminit
kernel_physical_mapping_remove(unsigned long start, unsigned long end)
{
start = (unsigned long)__va(start);
end = (unsigned long)__va(end);
remove_pagetable(start, end, true, NULL);
}
void __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
{
unsigned long start_pfn = start >> PAGE_SHIFT;
unsigned long nr_pages = size >> PAGE_SHIFT;
__remove_pages(start_pfn, nr_pages, altmap);
kernel_physical_mapping_remove(start, start + size);
}
#endif /* CONFIG_MEMORY_HOTPLUG */
static struct kcore_list kcore_vsyscall;
static void __init register_page_bootmem_info(void)
{
#if defined(CONFIG_NUMA) || defined(CONFIG_HUGETLB_PAGE_FREE_VMEMMAP)
int i;
for_each_online_node(i)
register_page_bootmem_info_node(NODE_DATA(i));
#endif
}
/*
* Pre-allocates page-table pages for the vmalloc area in the kernel page-table.
* Only the level which needs to be synchronized between all page-tables is
* allocated because the synchronization can be expensive.
*/
static void __init preallocate_vmalloc_pages(void)
{
unsigned long addr;
const char *lvl;
for (addr = VMALLOC_START; addr <= VMALLOC_END; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
pgd_t *pgd = pgd_offset_k(addr);
p4d_t *p4d;
pud_t *pud;
lvl = "p4d";
p4d = p4d_alloc(&init_mm, pgd, addr);
if (!p4d)
goto failed;
if (pgtable_l5_enabled())
continue;
/*
* The goal here is to allocate all possibly required
* hardware page tables pointed to by the top hardware
* level.
*
* On 4-level systems, the P4D layer is folded away and
* the above code does no preallocation. Below, go down
* to the pud _software_ level to ensure the second
* hardware level is allocated on 4-level systems too.
*/
lvl = "pud";
pud = pud_alloc(&init_mm, p4d, addr);
if (!pud)
goto failed;
}
return;
failed:
/*
* The pages have to be there now or they will be missing in
* process page-tables later.
*/
panic("Failed to pre-allocate %s pages for vmalloc area\n", lvl);
}
void __init mem_init(void)
{
pci_iommu_alloc();
/* clear_bss() already clear the empty_zero_page */
/* this will put all memory onto the freelists */
memblock_free_all();
after_bootmem = 1;
x86_init.hyper.init_after_bootmem();
/*
* Must be done after boot memory is put on freelist, because here we
* might set fields in deferred struct pages that have not yet been
* initialized, and memblock_free_all() initializes all the reserved
* deferred pages for us.
*/
register_page_bootmem_info();
/* Register memory areas for /proc/kcore */
if (get_gate_vma(&init_mm))
kclist_add(&kcore_vsyscall, (void *)VSYSCALL_ADDR, PAGE_SIZE, KCORE_USER);
preallocate_vmalloc_pages();
}
#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
int __init deferred_page_init_max_threads(const struct cpumask *node_cpumask)
{
/*
* More CPUs always led to greater speedups on tested systems, up to
* all the nodes' CPUs. Use all since the system is otherwise idle
* now.
*/
return max_t(int, cpumask_weight(node_cpumask), 1);
}
#endif
int kernel_set_to_readonly;
void mark_rodata_ro(void)
{
unsigned long start = PFN_ALIGN(_text);
unsigned long rodata_start = PFN_ALIGN(__start_rodata);
unsigned long end = (unsigned long)__end_rodata_hpage_align;
unsigned long text_end = PFN_ALIGN(_etext);
unsigned long rodata_end = PFN_ALIGN(__end_rodata);
unsigned long all_end;
printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
(end - start) >> 10);
set_memory_ro(start, (end - start) >> PAGE_SHIFT);
kernel_set_to_readonly = 1;
/*
* The rodata/data/bss/brk section (but not the kernel text!)
* should also be not-executable.
*
* We align all_end to PMD_SIZE because the existing mapping
* is a full PMD. If we would align _brk_end to PAGE_SIZE we
* split the PMD and the reminder between _brk_end and the end
* of the PMD will remain mapped executable.
*
* Any PMD which was setup after the one which covers _brk_end
* has been zapped already via cleanup_highmem().
*/
all_end = roundup((unsigned long)_brk_end, PMD_SIZE);
set_memory_nx(text_end, (all_end - text_end) >> PAGE_SHIFT);
set_ftrace_ops_ro();
#ifdef CONFIG_CPA_DEBUG
printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
set_memory_rw(start, (end-start) >> PAGE_SHIFT);
printk(KERN_INFO "Testing CPA: again\n");
set_memory_ro(start, (end-start) >> PAGE_SHIFT);
#endif
free_kernel_image_pages("unused kernel image (text/rodata gap)",
(void *)text_end, (void *)rodata_start);
free_kernel_image_pages("unused kernel image (rodata/data gap)",
(void *)rodata_end, (void *)_sdata);
debug_checkwx();
}
int kern_addr_valid(unsigned long addr)
{
unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
pgd_t *pgd;
p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
if (above != 0 && above != -1UL)
return 0;
pgd = pgd_offset_k(addr);
if (pgd_none(*pgd))
return 0;
p4d = p4d_offset(pgd, addr);
if (!p4d_present(*p4d))
return 0;
pud = pud_offset(p4d, addr);
if (!pud_present(*pud))
return 0;
if (pud_large(*pud))
return pfn_valid(pud_pfn(*pud));
pmd = pmd_offset(pud, addr);
if (!pmd_present(*pmd))
return 0;
if (pmd_large(*pmd))
return pfn_valid(pmd_pfn(*pmd));
pte = pte_offset_kernel(pmd, addr);
if (pte_none(*pte))
return 0;
return pfn_valid(pte_pfn(*pte));
}
/*
* Block size is the minimum amount of memory which can be hotplugged or
* hotremoved. It must be power of two and must be equal or larger than
* MIN_MEMORY_BLOCK_SIZE.
*/
#define MAX_BLOCK_SIZE (2UL << 30)
/* Amount of ram needed to start using large blocks */
#define MEM_SIZE_FOR_LARGE_BLOCK (64UL << 30)
/* Adjustable memory block size */
static unsigned long set_memory_block_size;
int __init set_memory_block_size_order(unsigned int order)
{
unsigned long size = 1UL << order;
if (size > MEM_SIZE_FOR_LARGE_BLOCK || size < MIN_MEMORY_BLOCK_SIZE)
return -EINVAL;
set_memory_block_size = size;
return 0;
}
static unsigned long probe_memory_block_size(void)
{
unsigned long boot_mem_end = max_pfn << PAGE_SHIFT;
unsigned long bz;
/* If memory block size has been set, then use it */
bz = set_memory_block_size;
if (bz)
goto done;
/* Use regular block if RAM is smaller than MEM_SIZE_FOR_LARGE_BLOCK */
if (boot_mem_end < MEM_SIZE_FOR_LARGE_BLOCK) {
bz = MIN_MEMORY_BLOCK_SIZE;
goto done;
}
/*
* Use max block size to minimize overhead on bare metal, where
* alignment for memory hotplug isn't a concern.
*/
if (!boot_cpu_has(X86_FEATURE_HYPERVISOR)) {
bz = MAX_BLOCK_SIZE;
goto done;
}
/* Find the largest allowed block size that aligns to memory end */
for (bz = MAX_BLOCK_SIZE; bz > MIN_MEMORY_BLOCK_SIZE; bz >>= 1) {
if (IS_ALIGNED(boot_mem_end, bz))
break;
}
done:
pr_info("x86/mm: Memory block size: %ldMB\n", bz >> 20);
return bz;
}
static unsigned long memory_block_size_probed;
unsigned long memory_block_size_bytes(void)
{
if (!memory_block_size_probed)
memory_block_size_probed = probe_memory_block_size();
return memory_block_size_probed;
}
#ifdef CONFIG_SPARSEMEM_VMEMMAP
/*
* Initialise the sparsemem vmemmap using huge-pages at the PMD level.
*/
static long __meminitdata addr_start, addr_end;
static void __meminitdata *p_start, *p_end;
static int __meminitdata node_start;
static int __meminit vmemmap_populate_hugepages(unsigned long start,
unsigned long end, int node, struct vmem_altmap *altmap)
{
unsigned long addr;
unsigned long next;
pgd_t *pgd;
p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;
for (addr = start; addr < end; addr = next) {
next = pmd_addr_end(addr, end);
pgd = vmemmap_pgd_populate(addr, node);
if (!pgd)
return -ENOMEM;
p4d = vmemmap_p4d_populate(pgd, addr, node);
if (!p4d)
return -ENOMEM;
pud = vmemmap_pud_populate(p4d, addr, node);
if (!pud)
return -ENOMEM;
pmd = pmd_offset(pud, addr);
if (pmd_none(*pmd)) {
void *p;
p = vmemmap_alloc_block_buf(PMD_SIZE, node, altmap);
if (p) {
pte_t entry;
entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
PAGE_KERNEL_LARGE);
set_pmd(pmd, __pmd(pte_val(entry)));
/* check to see if we have contiguous blocks */
if (p_end != p || node_start != node) {
if (p_start)
pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n",
addr_start, addr_end-1, p_start, p_end-1, node_start);
addr_start = addr;
node_start = node;
p_start = p;
}
addr_end = addr + PMD_SIZE;
p_end = p + PMD_SIZE;
if (!IS_ALIGNED(addr, PMD_SIZE) ||
!IS_ALIGNED(next, PMD_SIZE))
vmemmap_use_new_sub_pmd(addr, next);
continue;
} else if (altmap)
return -ENOMEM; /* no fallback */
} else if (pmd_large(*pmd)) {
vmemmap_verify((pte_t *)pmd, node, addr, next);
vmemmap_use_sub_pmd(addr, next);
continue;
}
if (vmemmap_populate_basepages(addr, next, node, NULL))
return -ENOMEM;
}
return 0;
}
int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
struct vmem_altmap *altmap)
{
int err;
VM_BUG_ON(!IS_ALIGNED(start, PAGE_SIZE));
VM_BUG_ON(!IS_ALIGNED(end, PAGE_SIZE));
if (end - start < PAGES_PER_SECTION * sizeof(struct page))
err = vmemmap_populate_basepages(start, end, node, NULL);
else if (boot_cpu_has(X86_FEATURE_PSE))
err = vmemmap_populate_hugepages(start, end, node, altmap);
else if (altmap) {
pr_err_once("%s: no cpu support for altmap allocations\n",
__func__);
err = -ENOMEM;
} else
err = vmemmap_populate_basepages(start, end, node, NULL);
if (!err)
sync_global_pgds(start, end - 1);
return err;
}
#ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE
void register_page_bootmem_memmap(unsigned long section_nr,
struct page *start_page, unsigned long nr_pages)
{
unsigned long addr = (unsigned long)start_page;
unsigned long end = (unsigned long)(start_page + nr_pages);
unsigned long next;
pgd_t *pgd;
p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;
unsigned int nr_pmd_pages;
struct page *page;
for (; addr < end; addr = next) {
pte_t *pte = NULL;
pgd = pgd_offset_k(addr);
if (pgd_none(*pgd)) {
next = (addr + PAGE_SIZE) & PAGE_MASK;
continue;
}
get_page_bootmem(section_nr, pgd_page(*pgd), MIX_SECTION_INFO);
p4d = p4d_offset(pgd, addr);
if (p4d_none(*p4d)) {
next = (addr + PAGE_SIZE) & PAGE_MASK;
continue;
}
get_page_bootmem(section_nr, p4d_page(*p4d), MIX_SECTION_INFO);
pud = pud_offset(p4d, addr);
if (pud_none(*pud)) {
next = (addr + PAGE_SIZE) & PAGE_MASK;
continue;
}
get_page_bootmem(section_nr, pud_page(*pud), MIX_SECTION_INFO);
if (!boot_cpu_has(X86_FEATURE_PSE)) {
next = (addr + PAGE_SIZE) & PAGE_MASK;
pmd = pmd_offset(pud, addr);
if (pmd_none(*pmd))
continue;
get_page_bootmem(section_nr, pmd_page(*pmd),
MIX_SECTION_INFO);
pte = pte_offset_kernel(pmd, addr);
if (pte_none(*pte))
continue;
get_page_bootmem(section_nr, pte_page(*pte),
SECTION_INFO);
} else {
next = pmd_addr_end(addr, end);
pmd = pmd_offset(pud, addr);
if (pmd_none(*pmd))
continue;
nr_pmd_pages = 1 << get_order(PMD_SIZE);
page = pmd_page(*pmd);
while (nr_pmd_pages--)
get_page_bootmem(section_nr, page++,
SECTION_INFO);
}
}
}
#endif
void __meminit vmemmap_populate_print_last(void)
{
if (p_start) {
pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n",
addr_start, addr_end-1, p_start, p_end-1, node_start);
p_start = NULL;
p_end = NULL;
node_start = 0;
}
}
#endif
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