1
linux/arch/riscv/mm/init.c
Björn Töpel 007480fe84
riscv: mm: Refactor create_linear_mapping_range() for memory hot add
Add a parameter to the direct map setup function, so it can be used in
arch_add_memory() later.

Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Björn Töpel <bjorn@rivosinc.com>
Link: https://lore.kernel.org/r/20240605114100.315918-5-bjorn@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-06-26 08:42:40 -07:00

1536 lines
44 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2012 Regents of the University of California
* Copyright (C) 2019 Western Digital Corporation or its affiliates.
* Copyright (C) 2020 FORTH-ICS/CARV
* Nick Kossifidis <mick@ics.forth.gr>
*/
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/memblock.h>
#include <linux/initrd.h>
#include <linux/swap.h>
#include <linux/swiotlb.h>
#include <linux/sizes.h>
#include <linux/of_fdt.h>
#include <linux/of_reserved_mem.h>
#include <linux/libfdt.h>
#include <linux/set_memory.h>
#include <linux/dma-map-ops.h>
#include <linux/crash_dump.h>
#include <linux/hugetlb.h>
#ifdef CONFIG_RELOCATABLE
#include <linux/elf.h>
#endif
#include <linux/kfence.h>
#include <linux/execmem.h>
#include <asm/fixmap.h>
#include <asm/io.h>
#include <asm/kasan.h>
#include <asm/numa.h>
#include <asm/pgtable.h>
#include <asm/sections.h>
#include <asm/soc.h>
#include <asm/tlbflush.h>
#include "../kernel/head.h"
struct kernel_mapping kernel_map __ro_after_init;
EXPORT_SYMBOL(kernel_map);
#ifdef CONFIG_XIP_KERNEL
#define kernel_map (*(struct kernel_mapping *)XIP_FIXUP(&kernel_map))
#endif
#ifdef CONFIG_64BIT
u64 satp_mode __ro_after_init = !IS_ENABLED(CONFIG_XIP_KERNEL) ? SATP_MODE_57 : SATP_MODE_39;
#else
u64 satp_mode __ro_after_init = SATP_MODE_32;
#endif
EXPORT_SYMBOL(satp_mode);
#ifdef CONFIG_64BIT
bool pgtable_l4_enabled __ro_after_init = !IS_ENABLED(CONFIG_XIP_KERNEL);
bool pgtable_l5_enabled __ro_after_init = !IS_ENABLED(CONFIG_XIP_KERNEL);
EXPORT_SYMBOL(pgtable_l4_enabled);
EXPORT_SYMBOL(pgtable_l5_enabled);
#endif
phys_addr_t phys_ram_base __ro_after_init;
EXPORT_SYMBOL(phys_ram_base);
unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
__page_aligned_bss;
EXPORT_SYMBOL(empty_zero_page);
extern char _start[];
void *_dtb_early_va __initdata;
uintptr_t _dtb_early_pa __initdata;
phys_addr_t dma32_phys_limit __initdata;
static void __init zone_sizes_init(void)
{
unsigned long max_zone_pfns[MAX_NR_ZONES] = { 0, };
#ifdef CONFIG_ZONE_DMA32
max_zone_pfns[ZONE_DMA32] = PFN_DOWN(dma32_phys_limit);
#endif
max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
free_area_init(max_zone_pfns);
}
#if defined(CONFIG_MMU) && defined(CONFIG_DEBUG_VM)
#define LOG2_SZ_1K ilog2(SZ_1K)
#define LOG2_SZ_1M ilog2(SZ_1M)
#define LOG2_SZ_1G ilog2(SZ_1G)
#define LOG2_SZ_1T ilog2(SZ_1T)
static inline void print_mlk(char *name, unsigned long b, unsigned long t)
{
pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld kB)\n", name, b, t,
(((t) - (b)) >> LOG2_SZ_1K));
}
static inline void print_mlm(char *name, unsigned long b, unsigned long t)
{
pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld MB)\n", name, b, t,
(((t) - (b)) >> LOG2_SZ_1M));
}
static inline void print_mlg(char *name, unsigned long b, unsigned long t)
{
pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld GB)\n", name, b, t,
(((t) - (b)) >> LOG2_SZ_1G));
}
#ifdef CONFIG_64BIT
static inline void print_mlt(char *name, unsigned long b, unsigned long t)
{
pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld TB)\n", name, b, t,
(((t) - (b)) >> LOG2_SZ_1T));
}
#else
#define print_mlt(n, b, t) do {} while (0)
#endif
static inline void print_ml(char *name, unsigned long b, unsigned long t)
{
unsigned long diff = t - b;
if (IS_ENABLED(CONFIG_64BIT) && (diff >> LOG2_SZ_1T) >= 10)
print_mlt(name, b, t);
else if ((diff >> LOG2_SZ_1G) >= 10)
print_mlg(name, b, t);
else if ((diff >> LOG2_SZ_1M) >= 10)
print_mlm(name, b, t);
else
print_mlk(name, b, t);
}
static void __init print_vm_layout(void)
{
pr_notice("Virtual kernel memory layout:\n");
print_ml("fixmap", (unsigned long)FIXADDR_START,
(unsigned long)FIXADDR_TOP);
print_ml("pci io", (unsigned long)PCI_IO_START,
(unsigned long)PCI_IO_END);
print_ml("vmemmap", (unsigned long)VMEMMAP_START,
(unsigned long)VMEMMAP_END);
print_ml("vmalloc", (unsigned long)VMALLOC_START,
(unsigned long)VMALLOC_END);
#ifdef CONFIG_64BIT
print_ml("modules", (unsigned long)MODULES_VADDR,
(unsigned long)MODULES_END);
#endif
print_ml("lowmem", (unsigned long)PAGE_OFFSET,
(unsigned long)high_memory);
if (IS_ENABLED(CONFIG_64BIT)) {
#ifdef CONFIG_KASAN
print_ml("kasan", KASAN_SHADOW_START, KASAN_SHADOW_END);
#endif
print_ml("kernel", (unsigned long)kernel_map.virt_addr,
(unsigned long)ADDRESS_SPACE_END);
}
}
#else
static void print_vm_layout(void) { }
#endif /* CONFIG_DEBUG_VM */
void __init mem_init(void)
{
bool swiotlb = max_pfn > PFN_DOWN(dma32_phys_limit);
#ifdef CONFIG_FLATMEM
BUG_ON(!mem_map);
#endif /* CONFIG_FLATMEM */
if (IS_ENABLED(CONFIG_DMA_BOUNCE_UNALIGNED_KMALLOC) && !swiotlb &&
dma_cache_alignment != 1) {
/*
* If no bouncing needed for ZONE_DMA, allocate 1MB swiotlb
* buffer per 1GB of RAM for kmalloc() bouncing on
* non-coherent platforms.
*/
unsigned long size =
DIV_ROUND_UP(memblock_phys_mem_size(), 1024);
swiotlb_adjust_size(min(swiotlb_size_or_default(), size));
swiotlb = true;
}
swiotlb_init(swiotlb, SWIOTLB_VERBOSE);
memblock_free_all();
print_vm_layout();
}
/* Limit the memory size via mem. */
static phys_addr_t memory_limit;
#ifdef CONFIG_XIP_KERNEL
#define memory_limit (*(phys_addr_t *)XIP_FIXUP(&memory_limit))
#endif /* CONFIG_XIP_KERNEL */
static int __init early_mem(char *p)
{
u64 size;
if (!p)
return 1;
size = memparse(p, &p) & PAGE_MASK;
memory_limit = min_t(u64, size, memory_limit);
pr_notice("Memory limited to %lldMB\n", (u64)memory_limit >> 20);
return 0;
}
early_param("mem", early_mem);
static void __init setup_bootmem(void)
{
phys_addr_t vmlinux_end = __pa_symbol(&_end);
phys_addr_t max_mapped_addr;
phys_addr_t phys_ram_end, vmlinux_start;
if (IS_ENABLED(CONFIG_XIP_KERNEL))
vmlinux_start = __pa_symbol(&_sdata);
else
vmlinux_start = __pa_symbol(&_start);
memblock_enforce_memory_limit(memory_limit);
/*
* Make sure we align the reservation on PMD_SIZE since we will
* map the kernel in the linear mapping as read-only: we do not want
* any allocation to happen between _end and the next pmd aligned page.
*/
if (IS_ENABLED(CONFIG_64BIT) && IS_ENABLED(CONFIG_STRICT_KERNEL_RWX))
vmlinux_end = (vmlinux_end + PMD_SIZE - 1) & PMD_MASK;
/*
* Reserve from the start of the kernel to the end of the kernel
*/
memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start);
phys_ram_end = memblock_end_of_DRAM();
/*
* Make sure we align the start of the memory on a PMD boundary so that
* at worst, we map the linear mapping with PMD mappings.
*/
if (!IS_ENABLED(CONFIG_XIP_KERNEL))
phys_ram_base = memblock_start_of_DRAM() & PMD_MASK;
/*
* In 64-bit, any use of __va/__pa before this point is wrong as we
* did not know the start of DRAM before.
*/
if (IS_ENABLED(CONFIG_64BIT) && IS_ENABLED(CONFIG_MMU))
kernel_map.va_pa_offset = PAGE_OFFSET - phys_ram_base;
/*
* memblock allocator is not aware of the fact that last 4K bytes of
* the addressable memory can not be mapped because of IS_ERR_VALUE
* macro. Make sure that last 4k bytes are not usable by memblock
* if end of dram is equal to maximum addressable memory. For 64-bit
* kernel, this problem can't happen here as the end of the virtual
* address space is occupied by the kernel mapping then this check must
* be done as soon as the kernel mapping base address is determined.
*/
if (!IS_ENABLED(CONFIG_64BIT)) {
max_mapped_addr = __pa(~(ulong)0);
if (max_mapped_addr == (phys_ram_end - 1))
memblock_set_current_limit(max_mapped_addr - 4096);
}
min_low_pfn = PFN_UP(phys_ram_base);
max_low_pfn = max_pfn = PFN_DOWN(phys_ram_end);
high_memory = (void *)(__va(PFN_PHYS(max_low_pfn)));
dma32_phys_limit = min(4UL * SZ_1G, (unsigned long)PFN_PHYS(max_low_pfn));
set_max_mapnr(max_low_pfn - ARCH_PFN_OFFSET);
reserve_initrd_mem();
/*
* No allocation should be done before reserving the memory as defined
* in the device tree, otherwise the allocation could end up in a
* reserved region.
*/
early_init_fdt_scan_reserved_mem();
/*
* If DTB is built in, no need to reserve its memblock.
* Otherwise, do reserve it but avoid using
* early_init_fdt_reserve_self() since __pa() does
* not work for DTB pointers that are fixmap addresses
*/
if (!IS_ENABLED(CONFIG_BUILTIN_DTB))
memblock_reserve(dtb_early_pa, fdt_totalsize(dtb_early_va));
dma_contiguous_reserve(dma32_phys_limit);
if (IS_ENABLED(CONFIG_64BIT))
hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
}
#ifdef CONFIG_MMU
struct pt_alloc_ops pt_ops __meminitdata;
pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
pgd_t trampoline_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
static pte_t fixmap_pte[PTRS_PER_PTE] __page_aligned_bss;
pgd_t early_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
#ifdef CONFIG_XIP_KERNEL
#define pt_ops (*(struct pt_alloc_ops *)XIP_FIXUP(&pt_ops))
#define trampoline_pg_dir ((pgd_t *)XIP_FIXUP(trampoline_pg_dir))
#define fixmap_pte ((pte_t *)XIP_FIXUP(fixmap_pte))
#define early_pg_dir ((pgd_t *)XIP_FIXUP(early_pg_dir))
#endif /* CONFIG_XIP_KERNEL */
static const pgprot_t protection_map[16] = {
[VM_NONE] = PAGE_NONE,
[VM_READ] = PAGE_READ,
[VM_WRITE] = PAGE_COPY,
[VM_WRITE | VM_READ] = PAGE_COPY,
[VM_EXEC] = PAGE_EXEC,
[VM_EXEC | VM_READ] = PAGE_READ_EXEC,
[VM_EXEC | VM_WRITE] = PAGE_COPY_EXEC,
[VM_EXEC | VM_WRITE | VM_READ] = PAGE_COPY_EXEC,
[VM_SHARED] = PAGE_NONE,
[VM_SHARED | VM_READ] = PAGE_READ,
[VM_SHARED | VM_WRITE] = PAGE_SHARED,
[VM_SHARED | VM_WRITE | VM_READ] = PAGE_SHARED,
[VM_SHARED | VM_EXEC] = PAGE_EXEC,
[VM_SHARED | VM_EXEC | VM_READ] = PAGE_READ_EXEC,
[VM_SHARED | VM_EXEC | VM_WRITE] = PAGE_SHARED_EXEC,
[VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = PAGE_SHARED_EXEC
};
DECLARE_VM_GET_PAGE_PROT
void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot)
{
unsigned long addr = __fix_to_virt(idx);
pte_t *ptep;
BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses);
ptep = &fixmap_pte[pte_index(addr)];
if (pgprot_val(prot))
set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, prot));
else
pte_clear(&init_mm, addr, ptep);
local_flush_tlb_page(addr);
}
static inline pte_t *__init get_pte_virt_early(phys_addr_t pa)
{
return (pte_t *)((uintptr_t)pa);
}
static inline pte_t *__init get_pte_virt_fixmap(phys_addr_t pa)
{
clear_fixmap(FIX_PTE);
return (pte_t *)set_fixmap_offset(FIX_PTE, pa);
}
static inline pte_t *__meminit get_pte_virt_late(phys_addr_t pa)
{
return (pte_t *) __va(pa);
}
static inline phys_addr_t __init alloc_pte_early(uintptr_t va)
{
/*
* We only create PMD or PGD early mappings so we
* should never reach here with MMU disabled.
*/
BUG();
}
static inline phys_addr_t __init alloc_pte_fixmap(uintptr_t va)
{
return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
}
static phys_addr_t __meminit alloc_pte_late(uintptr_t va)
{
struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL & ~__GFP_HIGHMEM, 0);
BUG_ON(!ptdesc || !pagetable_pte_ctor(ptdesc));
return __pa((pte_t *)ptdesc_address(ptdesc));
}
static void __meminit create_pte_mapping(pte_t *ptep, uintptr_t va, phys_addr_t pa, phys_addr_t sz,
pgprot_t prot)
{
uintptr_t pte_idx = pte_index(va);
BUG_ON(sz != PAGE_SIZE);
if (pte_none(ptep[pte_idx]))
ptep[pte_idx] = pfn_pte(PFN_DOWN(pa), prot);
}
#ifndef __PAGETABLE_PMD_FOLDED
static pmd_t trampoline_pmd[PTRS_PER_PMD] __page_aligned_bss;
static pmd_t fixmap_pmd[PTRS_PER_PMD] __page_aligned_bss;
static pmd_t early_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZE);
#ifdef CONFIG_XIP_KERNEL
#define trampoline_pmd ((pmd_t *)XIP_FIXUP(trampoline_pmd))
#define fixmap_pmd ((pmd_t *)XIP_FIXUP(fixmap_pmd))
#define early_pmd ((pmd_t *)XIP_FIXUP(early_pmd))
#endif /* CONFIG_XIP_KERNEL */
static p4d_t trampoline_p4d[PTRS_PER_P4D] __page_aligned_bss;
static p4d_t fixmap_p4d[PTRS_PER_P4D] __page_aligned_bss;
static p4d_t early_p4d[PTRS_PER_P4D] __initdata __aligned(PAGE_SIZE);
#ifdef CONFIG_XIP_KERNEL
#define trampoline_p4d ((p4d_t *)XIP_FIXUP(trampoline_p4d))
#define fixmap_p4d ((p4d_t *)XIP_FIXUP(fixmap_p4d))
#define early_p4d ((p4d_t *)XIP_FIXUP(early_p4d))
#endif /* CONFIG_XIP_KERNEL */
static pud_t trampoline_pud[PTRS_PER_PUD] __page_aligned_bss;
static pud_t fixmap_pud[PTRS_PER_PUD] __page_aligned_bss;
static pud_t early_pud[PTRS_PER_PUD] __initdata __aligned(PAGE_SIZE);
#ifdef CONFIG_XIP_KERNEL
#define trampoline_pud ((pud_t *)XIP_FIXUP(trampoline_pud))
#define fixmap_pud ((pud_t *)XIP_FIXUP(fixmap_pud))
#define early_pud ((pud_t *)XIP_FIXUP(early_pud))
#endif /* CONFIG_XIP_KERNEL */
static pmd_t *__init get_pmd_virt_early(phys_addr_t pa)
{
/* Before MMU is enabled */
return (pmd_t *)((uintptr_t)pa);
}
static pmd_t *__init get_pmd_virt_fixmap(phys_addr_t pa)
{
clear_fixmap(FIX_PMD);
return (pmd_t *)set_fixmap_offset(FIX_PMD, pa);
}
static pmd_t *__meminit get_pmd_virt_late(phys_addr_t pa)
{
return (pmd_t *) __va(pa);
}
static phys_addr_t __init alloc_pmd_early(uintptr_t va)
{
BUG_ON((va - kernel_map.virt_addr) >> PUD_SHIFT);
return (uintptr_t)early_pmd;
}
static phys_addr_t __init alloc_pmd_fixmap(uintptr_t va)
{
return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
}
static phys_addr_t __meminit alloc_pmd_late(uintptr_t va)
{
struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL & ~__GFP_HIGHMEM, 0);
BUG_ON(!ptdesc || !pagetable_pmd_ctor(ptdesc));
return __pa((pmd_t *)ptdesc_address(ptdesc));
}
static void __meminit create_pmd_mapping(pmd_t *pmdp,
uintptr_t va, phys_addr_t pa,
phys_addr_t sz, pgprot_t prot)
{
pte_t *ptep;
phys_addr_t pte_phys;
uintptr_t pmd_idx = pmd_index(va);
if (sz == PMD_SIZE) {
if (pmd_none(pmdp[pmd_idx]))
pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pa), prot);
return;
}
if (pmd_none(pmdp[pmd_idx])) {
pte_phys = pt_ops.alloc_pte(va);
pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pte_phys), PAGE_TABLE);
ptep = pt_ops.get_pte_virt(pte_phys);
memset(ptep, 0, PAGE_SIZE);
} else {
pte_phys = PFN_PHYS(_pmd_pfn(pmdp[pmd_idx]));
ptep = pt_ops.get_pte_virt(pte_phys);
}
create_pte_mapping(ptep, va, pa, sz, prot);
}
static pud_t *__init get_pud_virt_early(phys_addr_t pa)
{
return (pud_t *)((uintptr_t)pa);
}
static pud_t *__init get_pud_virt_fixmap(phys_addr_t pa)
{
clear_fixmap(FIX_PUD);
return (pud_t *)set_fixmap_offset(FIX_PUD, pa);
}
static pud_t *__meminit get_pud_virt_late(phys_addr_t pa)
{
return (pud_t *)__va(pa);
}
static phys_addr_t __init alloc_pud_early(uintptr_t va)
{
/* Only one PUD is available for early mapping */
BUG_ON((va - kernel_map.virt_addr) >> PGDIR_SHIFT);
return (uintptr_t)early_pud;
}
static phys_addr_t __init alloc_pud_fixmap(uintptr_t va)
{
return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
}
static phys_addr_t __meminit alloc_pud_late(uintptr_t va)
{
unsigned long vaddr;
vaddr = __get_free_page(GFP_KERNEL);
BUG_ON(!vaddr);
return __pa(vaddr);
}
static p4d_t *__init get_p4d_virt_early(phys_addr_t pa)
{
return (p4d_t *)((uintptr_t)pa);
}
static p4d_t *__init get_p4d_virt_fixmap(phys_addr_t pa)
{
clear_fixmap(FIX_P4D);
return (p4d_t *)set_fixmap_offset(FIX_P4D, pa);
}
static p4d_t *__meminit get_p4d_virt_late(phys_addr_t pa)
{
return (p4d_t *)__va(pa);
}
static phys_addr_t __init alloc_p4d_early(uintptr_t va)
{
/* Only one P4D is available for early mapping */
BUG_ON((va - kernel_map.virt_addr) >> PGDIR_SHIFT);
return (uintptr_t)early_p4d;
}
static phys_addr_t __init alloc_p4d_fixmap(uintptr_t va)
{
return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
}
static phys_addr_t __meminit alloc_p4d_late(uintptr_t va)
{
unsigned long vaddr;
vaddr = __get_free_page(GFP_KERNEL);
BUG_ON(!vaddr);
return __pa(vaddr);
}
static void __meminit create_pud_mapping(pud_t *pudp, uintptr_t va, phys_addr_t pa, phys_addr_t sz,
pgprot_t prot)
{
pmd_t *nextp;
phys_addr_t next_phys;
uintptr_t pud_index = pud_index(va);
if (sz == PUD_SIZE) {
if (pud_val(pudp[pud_index]) == 0)
pudp[pud_index] = pfn_pud(PFN_DOWN(pa), prot);
return;
}
if (pud_val(pudp[pud_index]) == 0) {
next_phys = pt_ops.alloc_pmd(va);
pudp[pud_index] = pfn_pud(PFN_DOWN(next_phys), PAGE_TABLE);
nextp = pt_ops.get_pmd_virt(next_phys);
memset(nextp, 0, PAGE_SIZE);
} else {
next_phys = PFN_PHYS(_pud_pfn(pudp[pud_index]));
nextp = pt_ops.get_pmd_virt(next_phys);
}
create_pmd_mapping(nextp, va, pa, sz, prot);
}
static void __meminit create_p4d_mapping(p4d_t *p4dp, uintptr_t va, phys_addr_t pa, phys_addr_t sz,
pgprot_t prot)
{
pud_t *nextp;
phys_addr_t next_phys;
uintptr_t p4d_index = p4d_index(va);
if (sz == P4D_SIZE) {
if (p4d_val(p4dp[p4d_index]) == 0)
p4dp[p4d_index] = pfn_p4d(PFN_DOWN(pa), prot);
return;
}
if (p4d_val(p4dp[p4d_index]) == 0) {
next_phys = pt_ops.alloc_pud(va);
p4dp[p4d_index] = pfn_p4d(PFN_DOWN(next_phys), PAGE_TABLE);
nextp = pt_ops.get_pud_virt(next_phys);
memset(nextp, 0, PAGE_SIZE);
} else {
next_phys = PFN_PHYS(_p4d_pfn(p4dp[p4d_index]));
nextp = pt_ops.get_pud_virt(next_phys);
}
create_pud_mapping(nextp, va, pa, sz, prot);
}
#define pgd_next_t p4d_t
#define alloc_pgd_next(__va) (pgtable_l5_enabled ? \
pt_ops.alloc_p4d(__va) : (pgtable_l4_enabled ? \
pt_ops.alloc_pud(__va) : pt_ops.alloc_pmd(__va)))
#define get_pgd_next_virt(__pa) (pgtable_l5_enabled ? \
pt_ops.get_p4d_virt(__pa) : (pgd_next_t *)(pgtable_l4_enabled ? \
pt_ops.get_pud_virt(__pa) : (pud_t *)pt_ops.get_pmd_virt(__pa)))
#define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \
(pgtable_l5_enabled ? \
create_p4d_mapping(__nextp, __va, __pa, __sz, __prot) : \
(pgtable_l4_enabled ? \
create_pud_mapping((pud_t *)__nextp, __va, __pa, __sz, __prot) : \
create_pmd_mapping((pmd_t *)__nextp, __va, __pa, __sz, __prot)))
#define fixmap_pgd_next (pgtable_l5_enabled ? \
(uintptr_t)fixmap_p4d : (pgtable_l4_enabled ? \
(uintptr_t)fixmap_pud : (uintptr_t)fixmap_pmd))
#define trampoline_pgd_next (pgtable_l5_enabled ? \
(uintptr_t)trampoline_p4d : (pgtable_l4_enabled ? \
(uintptr_t)trampoline_pud : (uintptr_t)trampoline_pmd))
#else
#define pgd_next_t pte_t
#define alloc_pgd_next(__va) pt_ops.alloc_pte(__va)
#define get_pgd_next_virt(__pa) pt_ops.get_pte_virt(__pa)
#define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \
create_pte_mapping(__nextp, __va, __pa, __sz, __prot)
#define fixmap_pgd_next ((uintptr_t)fixmap_pte)
#define create_p4d_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0)
#define create_pud_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0)
#define create_pmd_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0)
#endif /* __PAGETABLE_PMD_FOLDED */
void __meminit create_pgd_mapping(pgd_t *pgdp, uintptr_t va, phys_addr_t pa, phys_addr_t sz,
pgprot_t prot)
{
pgd_next_t *nextp;
phys_addr_t next_phys;
uintptr_t pgd_idx = pgd_index(va);
if (sz == PGDIR_SIZE) {
if (pgd_val(pgdp[pgd_idx]) == 0)
pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(pa), prot);
return;
}
if (pgd_val(pgdp[pgd_idx]) == 0) {
next_phys = alloc_pgd_next(va);
pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(next_phys), PAGE_TABLE);
nextp = get_pgd_next_virt(next_phys);
memset(nextp, 0, PAGE_SIZE);
} else {
next_phys = PFN_PHYS(_pgd_pfn(pgdp[pgd_idx]));
nextp = get_pgd_next_virt(next_phys);
}
create_pgd_next_mapping(nextp, va, pa, sz, prot);
}
static uintptr_t __meminit best_map_size(phys_addr_t pa, uintptr_t va, phys_addr_t size)
{
if (debug_pagealloc_enabled())
return PAGE_SIZE;
if (pgtable_l5_enabled &&
!(pa & (P4D_SIZE - 1)) && !(va & (P4D_SIZE - 1)) && size >= P4D_SIZE)
return P4D_SIZE;
if (pgtable_l4_enabled &&
!(pa & (PUD_SIZE - 1)) && !(va & (PUD_SIZE - 1)) && size >= PUD_SIZE)
return PUD_SIZE;
if (IS_ENABLED(CONFIG_64BIT) &&
!(pa & (PMD_SIZE - 1)) && !(va & (PMD_SIZE - 1)) && size >= PMD_SIZE)
return PMD_SIZE;
return PAGE_SIZE;
}
#ifdef CONFIG_XIP_KERNEL
#define phys_ram_base (*(phys_addr_t *)XIP_FIXUP(&phys_ram_base))
extern char _xiprom[], _exiprom[], __data_loc;
/* called from head.S with MMU off */
asmlinkage void __init __copy_data(void)
{
void *from = (void *)(&__data_loc);
void *to = (void *)CONFIG_PHYS_RAM_BASE;
size_t sz = (size_t)((uintptr_t)(&_end) - (uintptr_t)(&_sdata));
memcpy(to, from, sz);
}
#endif
#ifdef CONFIG_STRICT_KERNEL_RWX
static __meminit pgprot_t pgprot_from_va(uintptr_t va)
{
if (is_va_kernel_text(va))
return PAGE_KERNEL_READ_EXEC;
/*
* In 64-bit kernel, the kernel mapping is outside the linear mapping so
* we must protect its linear mapping alias from being executed and
* written.
* And rodata section is marked readonly in mark_rodata_ro.
*/
if (IS_ENABLED(CONFIG_64BIT) && is_va_kernel_lm_alias_text(va))
return PAGE_KERNEL_READ;
return PAGE_KERNEL;
}
void mark_rodata_ro(void)
{
set_kernel_memory(__start_rodata, _data, set_memory_ro);
if (IS_ENABLED(CONFIG_64BIT))
set_kernel_memory(lm_alias(__start_rodata), lm_alias(_data),
set_memory_ro);
}
#else
static __meminit pgprot_t pgprot_from_va(uintptr_t va)
{
if (IS_ENABLED(CONFIG_64BIT) && !is_kernel_mapping(va))
return PAGE_KERNEL;
return PAGE_KERNEL_EXEC;
}
#endif /* CONFIG_STRICT_KERNEL_RWX */
#if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL)
u64 __pi_set_satp_mode_from_cmdline(uintptr_t dtb_pa);
static void __init disable_pgtable_l5(void)
{
pgtable_l5_enabled = false;
kernel_map.page_offset = PAGE_OFFSET_L4;
satp_mode = SATP_MODE_48;
}
static void __init disable_pgtable_l4(void)
{
pgtable_l4_enabled = false;
kernel_map.page_offset = PAGE_OFFSET_L3;
satp_mode = SATP_MODE_39;
}
static int __init print_no4lvl(char *p)
{
pr_info("Disabled 4-level and 5-level paging");
return 0;
}
early_param("no4lvl", print_no4lvl);
static int __init print_no5lvl(char *p)
{
pr_info("Disabled 5-level paging");
return 0;
}
early_param("no5lvl", print_no5lvl);
static void __init set_mmap_rnd_bits_max(void)
{
mmap_rnd_bits_max = MMAP_VA_BITS - PAGE_SHIFT - 3;
}
/*
* There is a simple way to determine if 4-level is supported by the
* underlying hardware: establish 1:1 mapping in 4-level page table mode
* then read SATP to see if the configuration was taken into account
* meaning sv48 is supported.
*/
static __init void set_satp_mode(uintptr_t dtb_pa)
{
u64 identity_satp, hw_satp;
uintptr_t set_satp_mode_pmd = ((unsigned long)set_satp_mode) & PMD_MASK;
u64 satp_mode_cmdline = __pi_set_satp_mode_from_cmdline(dtb_pa);
if (satp_mode_cmdline == SATP_MODE_57) {
disable_pgtable_l5();
} else if (satp_mode_cmdline == SATP_MODE_48) {
disable_pgtable_l5();
disable_pgtable_l4();
return;
}
create_p4d_mapping(early_p4d,
set_satp_mode_pmd, (uintptr_t)early_pud,
P4D_SIZE, PAGE_TABLE);
create_pud_mapping(early_pud,
set_satp_mode_pmd, (uintptr_t)early_pmd,
PUD_SIZE, PAGE_TABLE);
/* Handle the case where set_satp_mode straddles 2 PMDs */
create_pmd_mapping(early_pmd,
set_satp_mode_pmd, set_satp_mode_pmd,
PMD_SIZE, PAGE_KERNEL_EXEC);
create_pmd_mapping(early_pmd,
set_satp_mode_pmd + PMD_SIZE,
set_satp_mode_pmd + PMD_SIZE,
PMD_SIZE, PAGE_KERNEL_EXEC);
retry:
create_pgd_mapping(early_pg_dir,
set_satp_mode_pmd,
pgtable_l5_enabled ?
(uintptr_t)early_p4d : (uintptr_t)early_pud,
PGDIR_SIZE, PAGE_TABLE);
identity_satp = PFN_DOWN((uintptr_t)&early_pg_dir) | satp_mode;
local_flush_tlb_all();
csr_write(CSR_SATP, identity_satp);
hw_satp = csr_swap(CSR_SATP, 0ULL);
local_flush_tlb_all();
if (hw_satp != identity_satp) {
if (pgtable_l5_enabled) {
disable_pgtable_l5();
memset(early_pg_dir, 0, PAGE_SIZE);
goto retry;
}
disable_pgtable_l4();
}
memset(early_pg_dir, 0, PAGE_SIZE);
memset(early_p4d, 0, PAGE_SIZE);
memset(early_pud, 0, PAGE_SIZE);
memset(early_pmd, 0, PAGE_SIZE);
}
#endif
/*
* setup_vm() is called from head.S with MMU-off.
*
* Following requirements should be honoured for setup_vm() to work
* correctly:
* 1) It should use PC-relative addressing for accessing kernel symbols.
* To achieve this we always use GCC cmodel=medany.
* 2) The compiler instrumentation for FTRACE will not work for setup_vm()
* so disable compiler instrumentation when FTRACE is enabled.
*
* Currently, the above requirements are honoured by using custom CFLAGS
* for init.o in mm/Makefile.
*/
#ifndef __riscv_cmodel_medany
#error "setup_vm() is called from head.S before relocate so it should not use absolute addressing."
#endif
#ifdef CONFIG_RELOCATABLE
extern unsigned long __rela_dyn_start, __rela_dyn_end;
static void __init relocate_kernel(void)
{
Elf64_Rela *rela = (Elf64_Rela *)&__rela_dyn_start;
/*
* This holds the offset between the linked virtual address and the
* relocated virtual address.
*/
uintptr_t reloc_offset = kernel_map.virt_addr - KERNEL_LINK_ADDR;
/*
* This holds the offset between kernel linked virtual address and
* physical address.
*/
uintptr_t va_kernel_link_pa_offset = KERNEL_LINK_ADDR - kernel_map.phys_addr;
for ( ; rela < (Elf64_Rela *)&__rela_dyn_end; rela++) {
Elf64_Addr addr = (rela->r_offset - va_kernel_link_pa_offset);
Elf64_Addr relocated_addr = rela->r_addend;
if (rela->r_info != R_RISCV_RELATIVE)
continue;
/*
* Make sure to not relocate vdso symbols like rt_sigreturn
* which are linked from the address 0 in vmlinux since
* vdso symbol addresses are actually used as an offset from
* mm->context.vdso in VDSO_OFFSET macro.
*/
if (relocated_addr >= KERNEL_LINK_ADDR)
relocated_addr += reloc_offset;
*(Elf64_Addr *)addr = relocated_addr;
}
}
#endif /* CONFIG_RELOCATABLE */
#ifdef CONFIG_XIP_KERNEL
static void __init create_kernel_page_table(pgd_t *pgdir,
__always_unused bool early)
{
uintptr_t va, end_va;
/* Map the flash resident part */
end_va = kernel_map.virt_addr + kernel_map.xiprom_sz;
for (va = kernel_map.virt_addr; va < end_va; va += PMD_SIZE)
create_pgd_mapping(pgdir, va,
kernel_map.xiprom + (va - kernel_map.virt_addr),
PMD_SIZE, PAGE_KERNEL_EXEC);
/* Map the data in RAM */
end_va = kernel_map.virt_addr + XIP_OFFSET + kernel_map.size;
for (va = kernel_map.virt_addr + XIP_OFFSET; va < end_va; va += PMD_SIZE)
create_pgd_mapping(pgdir, va,
kernel_map.phys_addr + (va - (kernel_map.virt_addr + XIP_OFFSET)),
PMD_SIZE, PAGE_KERNEL);
}
#else
static void __init create_kernel_page_table(pgd_t *pgdir, bool early)
{
uintptr_t va, end_va;
end_va = kernel_map.virt_addr + kernel_map.size;
for (va = kernel_map.virt_addr; va < end_va; va += PMD_SIZE)
create_pgd_mapping(pgdir, va,
kernel_map.phys_addr + (va - kernel_map.virt_addr),
PMD_SIZE,
early ?
PAGE_KERNEL_EXEC : pgprot_from_va(va));
}
#endif
/*
* Setup a 4MB mapping that encompasses the device tree: for 64-bit kernel,
* this means 2 PMD entries whereas for 32-bit kernel, this is only 1 PGDIR
* entry.
*/
static void __init create_fdt_early_page_table(uintptr_t fix_fdt_va,
uintptr_t dtb_pa)
{
#ifndef CONFIG_BUILTIN_DTB
uintptr_t pa = dtb_pa & ~(PMD_SIZE - 1);
/* Make sure the fdt fixmap address is always aligned on PMD size */
BUILD_BUG_ON(FIX_FDT % (PMD_SIZE / PAGE_SIZE));
/* In 32-bit only, the fdt lies in its own PGD */
if (!IS_ENABLED(CONFIG_64BIT)) {
create_pgd_mapping(early_pg_dir, fix_fdt_va,
pa, MAX_FDT_SIZE, PAGE_KERNEL);
} else {
create_pmd_mapping(fixmap_pmd, fix_fdt_va,
pa, PMD_SIZE, PAGE_KERNEL);
create_pmd_mapping(fixmap_pmd, fix_fdt_va + PMD_SIZE,
pa + PMD_SIZE, PMD_SIZE, PAGE_KERNEL);
}
dtb_early_va = (void *)fix_fdt_va + (dtb_pa & (PMD_SIZE - 1));
#else
/*
* For 64-bit kernel, __va can't be used since it would return a linear
* mapping address whereas dtb_early_va will be used before
* setup_vm_final installs the linear mapping. For 32-bit kernel, as the
* kernel is mapped in the linear mapping, that makes no difference.
*/
dtb_early_va = kernel_mapping_pa_to_va(dtb_pa);
#endif
dtb_early_pa = dtb_pa;
}
/*
* MMU is not enabled, the page tables are allocated directly using
* early_pmd/pud/p4d and the address returned is the physical one.
*/
static void __init pt_ops_set_early(void)
{
pt_ops.alloc_pte = alloc_pte_early;
pt_ops.get_pte_virt = get_pte_virt_early;
#ifndef __PAGETABLE_PMD_FOLDED
pt_ops.alloc_pmd = alloc_pmd_early;
pt_ops.get_pmd_virt = get_pmd_virt_early;
pt_ops.alloc_pud = alloc_pud_early;
pt_ops.get_pud_virt = get_pud_virt_early;
pt_ops.alloc_p4d = alloc_p4d_early;
pt_ops.get_p4d_virt = get_p4d_virt_early;
#endif
}
/*
* MMU is enabled but page table setup is not complete yet.
* fixmap page table alloc functions must be used as a means to temporarily
* map the allocated physical pages since the linear mapping does not exist yet.
*
* Note that this is called with MMU disabled, hence kernel_mapping_pa_to_va,
* but it will be used as described above.
*/
static void __init pt_ops_set_fixmap(void)
{
pt_ops.alloc_pte = kernel_mapping_pa_to_va(alloc_pte_fixmap);
pt_ops.get_pte_virt = kernel_mapping_pa_to_va(get_pte_virt_fixmap);
#ifndef __PAGETABLE_PMD_FOLDED
pt_ops.alloc_pmd = kernel_mapping_pa_to_va(alloc_pmd_fixmap);
pt_ops.get_pmd_virt = kernel_mapping_pa_to_va(get_pmd_virt_fixmap);
pt_ops.alloc_pud = kernel_mapping_pa_to_va(alloc_pud_fixmap);
pt_ops.get_pud_virt = kernel_mapping_pa_to_va(get_pud_virt_fixmap);
pt_ops.alloc_p4d = kernel_mapping_pa_to_va(alloc_p4d_fixmap);
pt_ops.get_p4d_virt = kernel_mapping_pa_to_va(get_p4d_virt_fixmap);
#endif
}
/*
* MMU is enabled and page table setup is complete, so from now, we can use
* generic page allocation functions to setup page table.
*/
static void __init pt_ops_set_late(void)
{
pt_ops.alloc_pte = alloc_pte_late;
pt_ops.get_pte_virt = get_pte_virt_late;
#ifndef __PAGETABLE_PMD_FOLDED
pt_ops.alloc_pmd = alloc_pmd_late;
pt_ops.get_pmd_virt = get_pmd_virt_late;
pt_ops.alloc_pud = alloc_pud_late;
pt_ops.get_pud_virt = get_pud_virt_late;
pt_ops.alloc_p4d = alloc_p4d_late;
pt_ops.get_p4d_virt = get_p4d_virt_late;
#endif
}
#ifdef CONFIG_RANDOMIZE_BASE
extern bool __init __pi_set_nokaslr_from_cmdline(uintptr_t dtb_pa);
extern u64 __init __pi_get_kaslr_seed(uintptr_t dtb_pa);
static int __init print_nokaslr(char *p)
{
pr_info("Disabled KASLR");
return 0;
}
early_param("nokaslr", print_nokaslr);
unsigned long kaslr_offset(void)
{
return kernel_map.virt_offset;
}
#endif
asmlinkage void __init setup_vm(uintptr_t dtb_pa)
{
pmd_t __maybe_unused fix_bmap_spmd, fix_bmap_epmd;
#ifdef CONFIG_RANDOMIZE_BASE
if (!__pi_set_nokaslr_from_cmdline(dtb_pa)) {
u64 kaslr_seed = __pi_get_kaslr_seed(dtb_pa);
u32 kernel_size = (uintptr_t)(&_end) - (uintptr_t)(&_start);
u32 nr_pos;
/*
* Compute the number of positions available: we are limited
* by the early page table that only has one PUD and we must
* be aligned on PMD_SIZE.
*/
nr_pos = (PUD_SIZE - kernel_size) / PMD_SIZE;
kernel_map.virt_offset = (kaslr_seed % nr_pos) * PMD_SIZE;
}
#endif
kernel_map.virt_addr = KERNEL_LINK_ADDR + kernel_map.virt_offset;
#ifdef CONFIG_XIP_KERNEL
#ifdef CONFIG_64BIT
kernel_map.page_offset = PAGE_OFFSET_L3;
#else
kernel_map.page_offset = _AC(CONFIG_PAGE_OFFSET, UL);
#endif
kernel_map.xiprom = (uintptr_t)CONFIG_XIP_PHYS_ADDR;
kernel_map.xiprom_sz = (uintptr_t)(&_exiprom) - (uintptr_t)(&_xiprom);
phys_ram_base = CONFIG_PHYS_RAM_BASE;
kernel_map.phys_addr = (uintptr_t)CONFIG_PHYS_RAM_BASE;
kernel_map.size = (uintptr_t)(&_end) - (uintptr_t)(&_sdata);
kernel_map.va_kernel_xip_pa_offset = kernel_map.virt_addr - kernel_map.xiprom;
#else
kernel_map.page_offset = _AC(CONFIG_PAGE_OFFSET, UL);
kernel_map.phys_addr = (uintptr_t)(&_start);
kernel_map.size = (uintptr_t)(&_end) - kernel_map.phys_addr;
#endif
#if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL)
set_satp_mode(dtb_pa);
set_mmap_rnd_bits_max();
#endif
/*
* In 64-bit, we defer the setup of va_pa_offset to setup_bootmem,
* where we have the system memory layout: this allows us to align
* the physical and virtual mappings and then make use of PUD/P4D/PGD
* for the linear mapping. This is only possible because the kernel
* mapping lies outside the linear mapping.
* In 32-bit however, as the kernel resides in the linear mapping,
* setup_vm_final can not change the mapping established here,
* otherwise the same kernel addresses would get mapped to different
* physical addresses (if the start of dram is different from the
* kernel physical address start).
*/
kernel_map.va_pa_offset = IS_ENABLED(CONFIG_64BIT) ?
0UL : PAGE_OFFSET - kernel_map.phys_addr;
kernel_map.va_kernel_pa_offset = kernel_map.virt_addr - kernel_map.phys_addr;
/*
* The default maximal physical memory size is KERN_VIRT_SIZE for 32-bit
* kernel, whereas for 64-bit kernel, the end of the virtual address
* space is occupied by the modules/BPF/kernel mappings which reduces
* the available size of the linear mapping.
*/
memory_limit = KERN_VIRT_SIZE - (IS_ENABLED(CONFIG_64BIT) ? SZ_4G : 0);
/* Sanity check alignment and size */
BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0);
BUG_ON((kernel_map.phys_addr % PMD_SIZE) != 0);
#ifdef CONFIG_64BIT
/*
* The last 4K bytes of the addressable memory can not be mapped because
* of IS_ERR_VALUE macro.
*/
BUG_ON((kernel_map.virt_addr + kernel_map.size) > ADDRESS_SPACE_END - SZ_4K);
#endif
#ifdef CONFIG_RELOCATABLE
/*
* Early page table uses only one PUD, which makes it possible
* to map PUD_SIZE aligned on PUD_SIZE: if the relocation offset
* makes the kernel cross over a PUD_SIZE boundary, raise a bug
* since a part of the kernel would not get mapped.
*/
BUG_ON(PUD_SIZE - (kernel_map.virt_addr & (PUD_SIZE - 1)) < kernel_map.size);
relocate_kernel();
#endif
apply_early_boot_alternatives();
pt_ops_set_early();
/* Setup early PGD for fixmap */
create_pgd_mapping(early_pg_dir, FIXADDR_START,
fixmap_pgd_next, PGDIR_SIZE, PAGE_TABLE);
#ifndef __PAGETABLE_PMD_FOLDED
/* Setup fixmap P4D and PUD */
if (pgtable_l5_enabled)
create_p4d_mapping(fixmap_p4d, FIXADDR_START,
(uintptr_t)fixmap_pud, P4D_SIZE, PAGE_TABLE);
/* Setup fixmap PUD and PMD */
if (pgtable_l4_enabled)
create_pud_mapping(fixmap_pud, FIXADDR_START,
(uintptr_t)fixmap_pmd, PUD_SIZE, PAGE_TABLE);
create_pmd_mapping(fixmap_pmd, FIXADDR_START,
(uintptr_t)fixmap_pte, PMD_SIZE, PAGE_TABLE);
/* Setup trampoline PGD and PMD */
create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr,
trampoline_pgd_next, PGDIR_SIZE, PAGE_TABLE);
if (pgtable_l5_enabled)
create_p4d_mapping(trampoline_p4d, kernel_map.virt_addr,
(uintptr_t)trampoline_pud, P4D_SIZE, PAGE_TABLE);
if (pgtable_l4_enabled)
create_pud_mapping(trampoline_pud, kernel_map.virt_addr,
(uintptr_t)trampoline_pmd, PUD_SIZE, PAGE_TABLE);
#ifdef CONFIG_XIP_KERNEL
create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr,
kernel_map.xiprom, PMD_SIZE, PAGE_KERNEL_EXEC);
#else
create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr,
kernel_map.phys_addr, PMD_SIZE, PAGE_KERNEL_EXEC);
#endif
#else
/* Setup trampoline PGD */
create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr,
kernel_map.phys_addr, PGDIR_SIZE, PAGE_KERNEL_EXEC);
#endif
/*
* Setup early PGD covering entire kernel which will allow
* us to reach paging_init(). We map all memory banks later
* in setup_vm_final() below.
*/
create_kernel_page_table(early_pg_dir, true);
/* Setup early mapping for FDT early scan */
create_fdt_early_page_table(__fix_to_virt(FIX_FDT), dtb_pa);
/*
* Bootime fixmap only can handle PMD_SIZE mapping. Thus, boot-ioremap
* range can not span multiple pmds.
*/
BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
!= (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));
#ifndef __PAGETABLE_PMD_FOLDED
/*
* Early ioremap fixmap is already created as it lies within first 2MB
* of fixmap region. We always map PMD_SIZE. Thus, both FIX_BTMAP_END
* FIX_BTMAP_BEGIN should lie in the same pmd. Verify that and warn
* the user if not.
*/
fix_bmap_spmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_BEGIN))];
fix_bmap_epmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_END))];
if (pmd_val(fix_bmap_spmd) != pmd_val(fix_bmap_epmd)) {
WARN_ON(1);
pr_warn("fixmap btmap start [%08lx] != end [%08lx]\n",
pmd_val(fix_bmap_spmd), pmd_val(fix_bmap_epmd));
pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",
fix_to_virt(FIX_BTMAP_BEGIN));
pr_warn("fix_to_virt(FIX_BTMAP_END): %08lx\n",
fix_to_virt(FIX_BTMAP_END));
pr_warn("FIX_BTMAP_END: %d\n", FIX_BTMAP_END);
pr_warn("FIX_BTMAP_BEGIN: %d\n", FIX_BTMAP_BEGIN);
}
#endif
pt_ops_set_fixmap();
}
static void __meminit create_linear_mapping_range(phys_addr_t start, phys_addr_t end,
uintptr_t fixed_map_size, const pgprot_t *pgprot)
{
phys_addr_t pa;
uintptr_t va, map_size;
for (pa = start; pa < end; pa += map_size) {
va = (uintptr_t)__va(pa);
map_size = fixed_map_size ? fixed_map_size :
best_map_size(pa, va, end - pa);
create_pgd_mapping(swapper_pg_dir, va, pa, map_size,
pgprot ? *pgprot : pgprot_from_va(va));
}
}
static void __init create_linear_mapping_page_table(void)
{
phys_addr_t start, end;
phys_addr_t kfence_pool __maybe_unused;
u64 i;
#ifdef CONFIG_STRICT_KERNEL_RWX
phys_addr_t ktext_start = __pa_symbol(_start);
phys_addr_t ktext_size = __init_data_begin - _start;
phys_addr_t krodata_start = __pa_symbol(__start_rodata);
phys_addr_t krodata_size = _data - __start_rodata;
/* Isolate kernel text and rodata so they don't get mapped with a PUD */
memblock_mark_nomap(ktext_start, ktext_size);
memblock_mark_nomap(krodata_start, krodata_size);
#endif
#ifdef CONFIG_KFENCE
/*
* kfence pool must be backed by PAGE_SIZE mappings, so allocate it
* before we setup the linear mapping so that we avoid using hugepages
* for this region.
*/
kfence_pool = memblock_phys_alloc(KFENCE_POOL_SIZE, PAGE_SIZE);
BUG_ON(!kfence_pool);
memblock_mark_nomap(kfence_pool, KFENCE_POOL_SIZE);
__kfence_pool = __va(kfence_pool);
#endif
/* Map all memory banks in the linear mapping */
for_each_mem_range(i, &start, &end) {
if (start >= end)
break;
if (start <= __pa(PAGE_OFFSET) &&
__pa(PAGE_OFFSET) < end)
start = __pa(PAGE_OFFSET);
if (end >= __pa(PAGE_OFFSET) + memory_limit)
end = __pa(PAGE_OFFSET) + memory_limit;
create_linear_mapping_range(start, end, 0, NULL);
}
#ifdef CONFIG_STRICT_KERNEL_RWX
create_linear_mapping_range(ktext_start, ktext_start + ktext_size, 0, NULL);
create_linear_mapping_range(krodata_start, krodata_start + krodata_size, 0, NULL);
memblock_clear_nomap(ktext_start, ktext_size);
memblock_clear_nomap(krodata_start, krodata_size);
#endif
#ifdef CONFIG_KFENCE
create_linear_mapping_range(kfence_pool, kfence_pool + KFENCE_POOL_SIZE, PAGE_SIZE, NULL);
memblock_clear_nomap(kfence_pool, KFENCE_POOL_SIZE);
#endif
}
static void __init setup_vm_final(void)
{
/* Setup swapper PGD for fixmap */
#if !defined(CONFIG_64BIT)
/*
* In 32-bit, the device tree lies in a pgd entry, so it must be copied
* directly in swapper_pg_dir in addition to the pgd entry that points
* to fixmap_pte.
*/
unsigned long idx = pgd_index(__fix_to_virt(FIX_FDT));
set_pgd(&swapper_pg_dir[idx], early_pg_dir[idx]);
#endif
create_pgd_mapping(swapper_pg_dir, FIXADDR_START,
__pa_symbol(fixmap_pgd_next),
PGDIR_SIZE, PAGE_TABLE);
/* Map the linear mapping */
create_linear_mapping_page_table();
/* Map the kernel */
if (IS_ENABLED(CONFIG_64BIT))
create_kernel_page_table(swapper_pg_dir, false);
#ifdef CONFIG_KASAN
kasan_swapper_init();
#endif
/* Clear fixmap PTE and PMD mappings */
clear_fixmap(FIX_PTE);
clear_fixmap(FIX_PMD);
clear_fixmap(FIX_PUD);
clear_fixmap(FIX_P4D);
/* Move to swapper page table */
csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | satp_mode);
local_flush_tlb_all();
pt_ops_set_late();
}
#else
asmlinkage void __init setup_vm(uintptr_t dtb_pa)
{
dtb_early_va = (void *)dtb_pa;
dtb_early_pa = dtb_pa;
}
static inline void setup_vm_final(void)
{
}
#endif /* CONFIG_MMU */
/*
* reserve_crashkernel() - reserves memory for crash kernel
*
* This function reserves memory area given in "crashkernel=" kernel command
* line parameter. The memory reserved is used by dump capture kernel when
* primary kernel is crashing.
*/
static void __init arch_reserve_crashkernel(void)
{
unsigned long long low_size = 0;
unsigned long long crash_base, crash_size;
char *cmdline = boot_command_line;
bool high = false;
int ret;
if (!IS_ENABLED(CONFIG_CRASH_RESERVE))
return;
ret = parse_crashkernel(cmdline, memblock_phys_mem_size(),
&crash_size, &crash_base,
&low_size, &high);
if (ret)
return;
reserve_crashkernel_generic(cmdline, crash_size, crash_base,
low_size, high);
}
void __init paging_init(void)
{
setup_bootmem();
setup_vm_final();
/* Depend on that Linear Mapping is ready */
memblock_allow_resize();
}
void __init misc_mem_init(void)
{
early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT);
arch_numa_init();
sparse_init();
#ifdef CONFIG_SPARSEMEM_VMEMMAP
/* The entire VMEMMAP region has been populated. Flush TLB for this region */
local_flush_tlb_kernel_range(VMEMMAP_START, VMEMMAP_END);
#endif
zone_sizes_init();
arch_reserve_crashkernel();
memblock_dump_all();
}
#ifdef CONFIG_SPARSEMEM_VMEMMAP
void __meminit vmemmap_set_pmd(pmd_t *pmd, void *p, int node,
unsigned long addr, unsigned long next)
{
pmd_set_huge(pmd, virt_to_phys(p), PAGE_KERNEL);
}
int __meminit vmemmap_check_pmd(pmd_t *pmdp, int node,
unsigned long addr, unsigned long next)
{
vmemmap_verify((pte_t *)pmdp, node, addr, next);
return 1;
}
int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
struct vmem_altmap *altmap)
{
/*
* Note that SPARSEMEM_VMEMMAP is only selected for rv64 and that we
* can't use hugepage mappings for 2-level page table because in case of
* memory hotplug, we are not able to update all the page tables with
* the new PMDs.
*/
return vmemmap_populate_hugepages(start, end, node, altmap);
}
#endif
#if defined(CONFIG_MMU) && defined(CONFIG_64BIT)
/*
* Pre-allocates page-table pages for a specific 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_pgd_pages_range(unsigned long start, unsigned long end,
const char *area)
{
unsigned long addr;
const char *lvl;
for (addr = start; addr < end && addr >= start; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
pgd_t *pgd = pgd_offset_k(addr);
p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;
lvl = "p4d";
p4d = p4d_alloc(&init_mm, pgd, addr);
if (!p4d)
goto failed;
if (pgtable_l5_enabled)
continue;
lvl = "pud";
pud = pud_alloc(&init_mm, p4d, addr);
if (!pud)
goto failed;
if (pgtable_l4_enabled)
continue;
lvl = "pmd";
pmd = pmd_alloc(&init_mm, pud, addr);
if (!pmd)
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 %s area\n", lvl, area);
}
#define PAGE_END KASAN_SHADOW_START
void __init pgtable_cache_init(void)
{
preallocate_pgd_pages_range(VMALLOC_START, VMALLOC_END, "vmalloc");
if (IS_ENABLED(CONFIG_MODULES))
preallocate_pgd_pages_range(MODULES_VADDR, MODULES_END, "bpf/modules");
if (IS_ENABLED(CONFIG_MEMORY_HOTPLUG)) {
preallocate_pgd_pages_range(VMEMMAP_START, VMEMMAP_END, "vmemmap");
preallocate_pgd_pages_range(PAGE_OFFSET, PAGE_END, "direct map");
if (IS_ENABLED(CONFIG_KASAN))
preallocate_pgd_pages_range(KASAN_SHADOW_START, KASAN_SHADOW_END, "kasan");
}
}
#endif
#ifdef CONFIG_EXECMEM
#ifdef CONFIG_MMU
static struct execmem_info execmem_info __ro_after_init;
struct execmem_info __init *execmem_arch_setup(void)
{
execmem_info = (struct execmem_info){
.ranges = {
[EXECMEM_DEFAULT] = {
.start = MODULES_VADDR,
.end = MODULES_END,
.pgprot = PAGE_KERNEL,
.alignment = 1,
},
[EXECMEM_KPROBES] = {
.start = VMALLOC_START,
.end = VMALLOC_END,
.pgprot = PAGE_KERNEL_READ_EXEC,
.alignment = 1,
},
[EXECMEM_BPF] = {
.start = BPF_JIT_REGION_START,
.end = BPF_JIT_REGION_END,
.pgprot = PAGE_KERNEL,
.alignment = PAGE_SIZE,
},
},
};
return &execmem_info;
}
#endif /* CONFIG_MMU */
#endif /* CONFIG_EXECMEM */