arm64: MMU initialisation

This patch contains the initialisation of the memory blocks, MMU
attributes and the memory map. Only five memory types are defined:
Device nGnRnE (equivalent to Strongly Ordered), Device nGnRE (classic
Device memory), Device GRE, Normal Non-cacheable and Normal Cacheable.
Cache policies are supported via the memory attributes register
(MAIR_EL1) and only affect the Normal Cacheable mappings.

This patch also adds the SPARSEMEM_VMEMMAP initialisation.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Olof Johansson <olof@lixom.net>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
This commit is contained in:
Catalin Marinas 2012-03-05 11:49:27 +00:00
parent 4f04d8f005
commit c1cc155261
3 changed files with 853 additions and 0 deletions

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/*
* Copyright (C) 2012 ARM Ltd.
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __ASM_MEMBLOCK_H
#define __ASM_MEMBLOCK_H
extern void arm64_memblock_init(void);
#endif

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arch/arm64/mm/init.c Normal file
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/*
* Based on arch/arm/mm/init.c
*
* Copyright (C) 1995-2005 Russell King
* Copyright (C) 2012 ARM Ltd.
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/errno.h>
#include <linux/swap.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/mman.h>
#include <linux/nodemask.h>
#include <linux/initrd.h>
#include <linux/gfp.h>
#include <linux/memblock.h>
#include <linux/sort.h>
#include <linux/of_fdt.h>
#include <asm/prom.h>
#include <asm/sections.h>
#include <asm/setup.h>
#include <asm/sizes.h>
#include <asm/tlb.h>
#include "mm.h"
static unsigned long phys_initrd_start __initdata = 0;
static unsigned long phys_initrd_size __initdata = 0;
phys_addr_t memstart_addr __read_mostly = 0;
void __init early_init_dt_setup_initrd_arch(unsigned long start,
unsigned long end)
{
phys_initrd_start = start;
phys_initrd_size = end - start;
}
static int __init early_initrd(char *p)
{
unsigned long start, 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);
#define MAX_DMA32_PFN ((4UL * 1024 * 1024 * 1024) >> PAGE_SHIFT)
static void __init zone_sizes_init(unsigned long min, unsigned long max)
{
struct memblock_region *reg;
unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
unsigned long max_dma32 = min;
memset(zone_size, 0, sizeof(zone_size));
#ifdef CONFIG_ZONE_DMA32
/* 4GB maximum for 32-bit only capable devices */
max_dma32 = min(max, MAX_DMA32_PFN);
zone_size[ZONE_DMA32] = max_dma32 - min;
#endif
zone_size[ZONE_NORMAL] = max - max_dma32;
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)
continue;
#ifdef CONFIG_ZONE_DMA32
if (start < max_dma32) {
unsigned long dma_end = min(end, max_dma32);
zhole_size[ZONE_DMA32] -= dma_end - start;
}
#endif
if (end > max_dma32) {
unsigned long normal_end = min(end, max);
unsigned long normal_start = max(start, max_dma32);
zhole_size[ZONE_NORMAL] -= normal_end - normal_start;
}
}
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_memory(pfn << PAGE_SHIFT);
}
EXPORT_SYMBOL(pfn_valid);
#endif
#ifndef CONFIG_SPARSEMEM
static void arm64_memory_present(void)
{
}
#else
static void arm64_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
void __init arm64_memblock_init(void)
{
u64 *reserve_map, base, size;
/* Register the kernel text, kernel data and initrd with memblock */
memblock_reserve(__pa(_text), _end - _text);
#ifdef CONFIG_BLK_DEV_INITRD
if (phys_initrd_size) {
memblock_reserve(phys_initrd_start, phys_initrd_size);
/* Now convert initrd to virtual addresses */
initrd_start = __phys_to_virt(phys_initrd_start);
initrd_end = initrd_start + phys_initrd_size;
}
#endif
/*
* Reserve the page tables. These are already in use,
* and can only be in node 0.
*/
memblock_reserve(__pa(swapper_pg_dir), SWAPPER_DIR_SIZE);
memblock_reserve(__pa(idmap_pg_dir), IDMAP_DIR_SIZE);
/* Reserve the dtb region */
memblock_reserve(virt_to_phys(initial_boot_params),
be32_to_cpu(initial_boot_params->totalsize));
/*
* Process the reserve map. This will probably overlap the initrd
* and dtb locations which are already reserved, but overlapping
* doesn't hurt anything
*/
reserve_map = ((void*)initial_boot_params) +
be32_to_cpu(initial_boot_params->off_mem_rsvmap);
while (1) {
base = be64_to_cpup(reserve_map++);
size = be64_to_cpup(reserve_map++);
if (!size)
break;
memblock_reserve(base, size);
}
memblock_allow_resize();
memblock_dump_all();
}
void __init bootmem_init(void)
{
unsigned long min, max;
min = PFN_UP(memblock_start_of_DRAM());
max = PFN_DOWN(memblock_end_of_DRAM());
/*
* Sparsemem tries to allocate bootmem in memory_present(), so must be
* done after the fixed reservations.
*/
arm64_memory_present();
sparse_init();
zone_sizes_init(min, max);
high_memory = __va((max << PAGE_SHIFT) - 1) + 1;
max_pfn = max_low_pfn = max;
}
static inline int free_area(unsigned long pfn, unsigned long end, char *s)
{
unsigned int pages = 0, size = (end - pfn) << (PAGE_SHIFT - 10);
for (; pfn < end; pfn++) {
struct page *page = pfn_to_page(pfn);
ClearPageReserved(page);
init_page_count(page);
__free_page(page);
pages++;
}
if (size && s)
pr_info("Freeing %s memory: %dK\n", s, size);
return pages;
}
/*
* Poison init memory with an undefined instruction (0x0).
*/
static inline void poison_init_mem(void *s, size_t count)
{
memset(s, 0, count);
}
#ifndef CONFIG_SPARSEMEM_VMEMMAP
static inline void free_memmap(unsigned long start_pfn, unsigned long end_pfn)
{
struct page *start_pg, *end_pg;
unsigned long 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 = (unsigned long)PAGE_ALIGN(__pa(start_pg));
pgend = (unsigned long)__pa(end_pg) & PAGE_MASK;
/*
* If there are free pages between these, free the section of the
* memmap array.
*/
if (pg < pgend)
free_bootmem(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;
for_each_memblock(memory, reg) {
start = __phys_to_pfn(reg->base);
#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));
#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(start + __phys_to_pfn(reg->size),
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
}
#endif /* !CONFIG_SPARSEMEM_VMEMMAP */
/*
* 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)
{
unsigned long reserved_pages, free_pages;
struct memblock_region *reg;
#if CONFIG_SWIOTLB
extern void __init arm64_swiotlb_init(size_t max_size);
arm64_swiotlb_init(max_pfn << (PAGE_SHIFT - 1));
#endif
max_mapnr = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map;
#ifndef CONFIG_SPARSEMEM_VMEMMAP
/* this will put all unused low memory onto the freelists */
free_unused_memmap();
#endif
totalram_pages += free_all_bootmem();
reserved_pages = free_pages = 0;
for_each_memblock(memory, reg) {
unsigned int pfn1, pfn2;
struct page *page, *end;
pfn1 = __phys_to_pfn(reg->base);
pfn2 = pfn1 + __phys_to_pfn(reg->size);
page = pfn_to_page(pfn1);
end = pfn_to_page(pfn2 - 1) + 1;
do {
if (PageReserved(page))
reserved_pages++;
else if (!page_count(page))
free_pages++;
page++;
} while (page < end);
}
/*
* Since our memory may not be contiguous, calculate the real number
* of pages we have in this system.
*/
pr_info("Memory:");
num_physpages = 0;
for_each_memblock(memory, reg) {
unsigned long pages = memblock_region_memory_end_pfn(reg) -
memblock_region_memory_base_pfn(reg);
num_physpages += pages;
printk(" %ldMB", pages >> (20 - PAGE_SHIFT));
}
printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
pr_notice("Memory: %luk/%luk available, %luk reserved\n",
nr_free_pages() << (PAGE_SHIFT-10),
free_pages << (PAGE_SHIFT-10),
reserved_pages << (PAGE_SHIFT-10));
#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"
" vmalloc : 0x%16lx - 0x%16lx (%6ld MB)\n"
#ifdef CONFIG_SPARSEMEM_VMEMMAP
" vmemmap : 0x%16lx - 0x%16lx (%6ld MB)\n"
#endif
" modules : 0x%16lx - 0x%16lx (%6ld MB)\n"
" memory : 0x%16lx - 0x%16lx (%6ld MB)\n"
" .init : 0x%p" " - 0x%p" " (%6ld kB)\n"
" .text : 0x%p" " - 0x%p" " (%6ld kB)\n"
" .data : 0x%p" " - 0x%p" " (%6ld kB)\n",
MLM(VMALLOC_START, VMALLOC_END),
#ifdef CONFIG_SPARSEMEM_VMEMMAP
MLM((unsigned long)virt_to_page(PAGE_OFFSET),
(unsigned long)virt_to_page(high_memory)),
#endif
MLM(MODULES_VADDR, MODULES_END),
MLM(PAGE_OFFSET, (unsigned long)high_memory),
MLK_ROUNDUP(__init_begin, __init_end),
MLK_ROUNDUP(_text, _etext),
MLK_ROUNDUP(_sdata, _edata));
#undef MLK
#undef MLM
#undef MLK_ROUNDUP
/*
* Check boundaries twice: Some fundamental inconsistencies can be
* detected at build time already.
*/
#ifdef CONFIG_COMPAT
BUILD_BUG_ON(TASK_SIZE_32 > TASK_SIZE_64);
#endif
BUILD_BUG_ON(TASK_SIZE_64 > MODULES_VADDR);
BUG_ON(TASK_SIZE_64 > MODULES_VADDR);
if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
extern int sysctl_overcommit_memory;
/*
* On a machine this small we won't get anywhere without
* overcommit, so turn it on by default.
*/
sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
}
}
void free_initmem(void)
{
poison_init_mem(__init_begin, __init_end - __init_begin);
totalram_pages += free_area(__phys_to_pfn(__pa(__init_begin)),
__phys_to_pfn(__pa(__init_end)),
"init");
}
#ifdef CONFIG_BLK_DEV_INITRD
static int keep_initrd;
void free_initrd_mem(unsigned long start, unsigned long end)
{
if (!keep_initrd) {
poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
totalram_pages += free_area(__phys_to_pfn(__pa(start)),
__phys_to_pfn(__pa(end)),
"initrd");
}
}
static int __init keepinitrd_setup(char *__unused)
{
keep_initrd = 1;
return 1;
}
__setup("keepinitrd", keepinitrd_setup);
#endif

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/*
* Based on arch/arm/mm/mmu.c
*
* Copyright (C) 1995-2005 Russell King
* Copyright (C) 2012 ARM Ltd.
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/export.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/mman.h>
#include <linux/nodemask.h>
#include <linux/memblock.h>
#include <linux/fs.h>
#include <asm/cputype.h>
#include <asm/sections.h>
#include <asm/setup.h>
#include <asm/sizes.h>
#include <asm/tlb.h>
#include <asm/mmu_context.h>
#include "mm.h"
/*
* Empty_zero_page is a special page that is used for zero-initialized data
* and COW.
*/
struct page *empty_zero_page;
EXPORT_SYMBOL(empty_zero_page);
pgprot_t pgprot_default;
EXPORT_SYMBOL(pgprot_default);
static pmdval_t prot_sect_kernel;
struct cachepolicy {
const char policy[16];
u64 mair;
u64 tcr;
};
static struct cachepolicy cache_policies[] __initdata = {
{
.policy = "uncached",
.mair = 0x44, /* inner, outer non-cacheable */
.tcr = TCR_IRGN_NC | TCR_ORGN_NC,
}, {
.policy = "writethrough",
.mair = 0xaa, /* inner, outer write-through, read-allocate */
.tcr = TCR_IRGN_WT | TCR_ORGN_WT,
}, {
.policy = "writeback",
.mair = 0xee, /* inner, outer write-back, read-allocate */
.tcr = TCR_IRGN_WBnWA | TCR_ORGN_WBnWA,
}
};
/*
* These are useful for identifying cache coherency problems by allowing the
* cache or the cache and writebuffer to be turned off. It changes the Normal
* memory caching attributes in the MAIR_EL1 register.
*/
static int __init early_cachepolicy(char *p)
{
int i;
u64 tmp;
for (i = 0; i < ARRAY_SIZE(cache_policies); i++) {
int len = strlen(cache_policies[i].policy);
if (memcmp(p, cache_policies[i].policy, len) == 0)
break;
}
if (i == ARRAY_SIZE(cache_policies)) {
pr_err("ERROR: unknown or unsupported cache policy: %s\n", p);
return 0;
}
flush_cache_all();
/*
* Modify MT_NORMAL attributes in MAIR_EL1.
*/
asm volatile(
" mrs %0, mair_el1\n"
" bfi %0, %1, #%2, #8\n"
" msr mair_el1, %0\n"
" isb\n"
: "=&r" (tmp)
: "r" (cache_policies[i].mair), "i" (MT_NORMAL * 8));
/*
* Modify TCR PTW cacheability attributes.
*/
asm volatile(
" mrs %0, tcr_el1\n"
" bic %0, %0, %2\n"
" orr %0, %0, %1\n"
" msr tcr_el1, %0\n"
" isb\n"
: "=&r" (tmp)
: "r" (cache_policies[i].tcr), "r" (TCR_IRGN_MASK | TCR_ORGN_MASK));
flush_cache_all();
return 0;
}
early_param("cachepolicy", early_cachepolicy);
/*
* Adjust the PMD section entries according to the CPU in use.
*/
static void __init init_mem_pgprot(void)
{
pteval_t default_pgprot;
int i;
default_pgprot = PTE_ATTRINDX(MT_NORMAL);
prot_sect_kernel = PMD_TYPE_SECT | PMD_SECT_AF | PMD_ATTRINDX(MT_NORMAL);
#ifdef CONFIG_SMP
/*
* Mark memory with the "shared" attribute for SMP systems
*/
default_pgprot |= PTE_SHARED;
prot_sect_kernel |= PMD_SECT_S;
#endif
for (i = 0; i < 16; i++) {
unsigned long v = pgprot_val(protection_map[i]);
protection_map[i] = __pgprot(v | default_pgprot);
}
pgprot_default = __pgprot(PTE_TYPE_PAGE | PTE_AF | default_pgprot);
}
pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
unsigned long size, pgprot_t vma_prot)
{
if (!pfn_valid(pfn))
return pgprot_noncached(vma_prot);
else if (file->f_flags & O_SYNC)
return pgprot_writecombine(vma_prot);
return vma_prot;
}
EXPORT_SYMBOL(phys_mem_access_prot);
static void __init *early_alloc(unsigned long sz)
{
void *ptr = __va(memblock_alloc(sz, sz));
memset(ptr, 0, sz);
return ptr;
}
static void __init alloc_init_pte(pmd_t *pmd, unsigned long addr,
unsigned long end, unsigned long pfn)
{
pte_t *pte;
if (pmd_none(*pmd)) {
pte = early_alloc(PTRS_PER_PTE * sizeof(pte_t));
__pmd_populate(pmd, __pa(pte), PMD_TYPE_TABLE);
}
BUG_ON(pmd_bad(*pmd));
pte = pte_offset_kernel(pmd, addr);
do {
set_pte(pte, pfn_pte(pfn, PAGE_KERNEL_EXEC));
pfn++;
} while (pte++, addr += PAGE_SIZE, addr != end);
}
static void __init alloc_init_pmd(pud_t *pud, unsigned long addr,
unsigned long end, phys_addr_t phys)
{
pmd_t *pmd;
unsigned long next;
/*
* Check for initial section mappings in the pgd/pud and remove them.
*/
if (pud_none(*pud) || pud_bad(*pud)) {
pmd = early_alloc(PTRS_PER_PMD * sizeof(pmd_t));
pud_populate(&init_mm, pud, pmd);
}
pmd = pmd_offset(pud, addr);
do {
next = pmd_addr_end(addr, end);
/* try section mapping first */
if (((addr | next | phys) & ~SECTION_MASK) == 0)
set_pmd(pmd, __pmd(phys | prot_sect_kernel));
else
alloc_init_pte(pmd, addr, next, __phys_to_pfn(phys));
phys += next - addr;
} while (pmd++, addr = next, addr != end);
}
static void __init alloc_init_pud(pgd_t *pgd, unsigned long addr,
unsigned long end, unsigned long phys)
{
pud_t *pud = pud_offset(pgd, addr);
unsigned long next;
do {
next = pud_addr_end(addr, end);
alloc_init_pmd(pud, addr, next, phys);
phys += next - addr;
} while (pud++, addr = next, addr != end);
}
/*
* Create the page directory entries and any necessary page tables for the
* mapping specified by 'md'.
*/
static void __init create_mapping(phys_addr_t phys, unsigned long virt,
phys_addr_t size)
{
unsigned long addr, length, end, next;
pgd_t *pgd;
if (virt < VMALLOC_START) {
pr_warning("BUG: not creating mapping for 0x%016llx at 0x%016lx - outside kernel range\n",
phys, virt);
return;
}
addr = virt & PAGE_MASK;
length = PAGE_ALIGN(size + (virt & ~PAGE_MASK));
pgd = pgd_offset_k(addr);
end = addr + length;
do {
next = pgd_addr_end(addr, end);
alloc_init_pud(pgd, addr, next, phys);
phys += next - addr;
} while (pgd++, addr = next, addr != end);
}
static void __init map_mem(void)
{
struct memblock_region *reg;
/* map all the memory banks */
for_each_memblock(memory, reg) {
phys_addr_t start = reg->base;
phys_addr_t end = start + reg->size;
if (start >= end)
break;
create_mapping(start, __phys_to_virt(start), end - start);
}
}
/*
* paging_init() sets up the page tables, initialises the zone memory
* maps and sets up the zero page.
*/
void __init paging_init(void)
{
void *zero_page;
/*
* Maximum PGDIR_SIZE addressable via the initial direct kernel
* mapping in swapper_pg_dir.
*/
memblock_set_current_limit((PHYS_OFFSET & PGDIR_MASK) + PGDIR_SIZE);
init_mem_pgprot();
map_mem();
/*
* Finally flush the caches and tlb to ensure that we're in a
* consistent state.
*/
flush_cache_all();
flush_tlb_all();
/* allocate the zero page. */
zero_page = early_alloc(PAGE_SIZE);
bootmem_init();
empty_zero_page = virt_to_page(zero_page);
__flush_dcache_page(empty_zero_page);
/*
* TTBR0 is only used for the identity mapping at this stage. Make it
* point to zero page to avoid speculatively fetching new entries.
*/
cpu_set_reserved_ttbr0();
flush_tlb_all();
}
/*
* Enable the identity mapping to allow the MMU disabling.
*/
void setup_mm_for_reboot(void)
{
cpu_switch_mm(idmap_pg_dir, &init_mm);
flush_tlb_all();
}
/*
* Check whether a kernel address is valid (derived from arch/x86/).
*/
int kern_addr_valid(unsigned long addr)
{
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
if ((((long)addr) >> VA_BITS) != -1UL)
return 0;
pgd = pgd_offset_k(addr);
if (pgd_none(*pgd))
return 0;
pud = pud_offset(pgd, addr);
if (pud_none(*pud))
return 0;
pmd = pmd_offset(pud, addr);
if (pmd_none(*pmd))
return 0;
pte = pte_offset_kernel(pmd, addr);
if (pte_none(*pte))
return 0;
return pfn_valid(pte_pfn(*pte));
}
#ifdef CONFIG_SPARSEMEM_VMEMMAP
#ifdef CONFIG_ARM64_64K_PAGES
int __meminit vmemmap_populate(struct page *start_page,
unsigned long size, int node)
{
return vmemmap_populate_basepages(start_page, size, node);
}
#else /* !CONFIG_ARM64_64K_PAGES */
int __meminit vmemmap_populate(struct page *start_page,
unsigned long size, int node)
{
unsigned long addr = (unsigned long)start_page;
unsigned long end = (unsigned long)(start_page + size);
unsigned long next;
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
do {
next = pmd_addr_end(addr, end);
pgd = vmemmap_pgd_populate(addr, node);
if (!pgd)
return -ENOMEM;
pud = vmemmap_pud_populate(pgd, addr, node);
if (!pud)
return -ENOMEM;
pmd = pmd_offset(pud, addr);
if (pmd_none(*pmd)) {
void *p = NULL;
p = vmemmap_alloc_block_buf(PMD_SIZE, node);
if (!p)
return -ENOMEM;
set_pmd(pmd, __pmd(__pa(p) | prot_sect_kernel));
} else
vmemmap_verify((pte_t *)pmd, node, addr, next);
} while (addr = next, addr != end);
return 0;
}
#endif /* CONFIG_ARM64_64K_PAGES */
#endif /* CONFIG_SPARSEMEM_VMEMMAP */