| /* |
| * 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/cache.h> |
| #include <linux/export.h> |
| #include <linux/kernel.h> |
| #include <linux/errno.h> |
| #include <linux/init.h> |
| #include <linux/ioport.h> |
| #include <linux/kexec.h> |
| #include <linux/libfdt.h> |
| #include <linux/mman.h> |
| #include <linux/nodemask.h> |
| #include <linux/memblock.h> |
| #include <linux/fs.h> |
| #include <linux/io.h> |
| #include <linux/mm.h> |
| #include <linux/vmalloc.h> |
| |
| #include <asm/barrier.h> |
| #include <asm/cputype.h> |
| #include <asm/fixmap.h> |
| #include <asm/kasan.h> |
| #include <asm/kernel-pgtable.h> |
| #include <asm/sections.h> |
| #include <asm/setup.h> |
| #include <asm/sizes.h> |
| #include <asm/tlb.h> |
| #include <asm/memblock.h> |
| #include <asm/mmu_context.h> |
| #include <asm/ptdump.h> |
| |
| #define NO_BLOCK_MAPPINGS BIT(0) |
| #define NO_CONT_MAPPINGS BIT(1) |
| |
| u64 idmap_t0sz = TCR_T0SZ(VA_BITS); |
| u64 idmap_ptrs_per_pgd = PTRS_PER_PGD; |
| |
| u64 kimage_voffset __ro_after_init; |
| EXPORT_SYMBOL(kimage_voffset); |
| |
| /* |
| * Empty_zero_page is a special page that is used for zero-initialized data |
| * and COW. |
| */ |
| unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss; |
| EXPORT_SYMBOL(empty_zero_page); |
| |
| static pte_t bm_pte[PTRS_PER_PTE] __page_aligned_bss; |
| static pmd_t bm_pmd[PTRS_PER_PMD] __page_aligned_bss __maybe_unused; |
| static pud_t bm_pud[PTRS_PER_PUD] __page_aligned_bss __maybe_unused; |
| |
| 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 phys_addr_t __init early_pgtable_alloc(void) |
| { |
| phys_addr_t phys; |
| void *ptr; |
| |
| phys = memblock_alloc(PAGE_SIZE, PAGE_SIZE); |
| |
| /* |
| * The FIX_{PGD,PUD,PMD} slots may be in active use, but the FIX_PTE |
| * slot will be free, so we can (ab)use the FIX_PTE slot to initialise |
| * any level of table. |
| */ |
| ptr = pte_set_fixmap(phys); |
| |
| memset(ptr, 0, PAGE_SIZE); |
| |
| /* |
| * Implicit barriers also ensure the zeroed page is visible to the page |
| * table walker |
| */ |
| pte_clear_fixmap(); |
| |
| return phys; |
| } |
| |
| static bool pgattr_change_is_safe(u64 old, u64 new) |
| { |
| /* |
| * The following mapping attributes may be updated in live |
| * kernel mappings without the need for break-before-make. |
| */ |
| static const pteval_t mask = PTE_PXN | PTE_RDONLY | PTE_WRITE; |
| |
| /* creating or taking down mappings is always safe */ |
| if (old == 0 || new == 0) |
| return true; |
| |
| /* live contiguous mappings may not be manipulated at all */ |
| if ((old | new) & PTE_CONT) |
| return false; |
| |
| /* Transitioning from Global to Non-Global is safe */ |
| if (((old ^ new) == PTE_NG) && (new & PTE_NG)) |
| return true; |
| |
| return ((old ^ new) & ~mask) == 0; |
| } |
| |
| static void init_pte(pmd_t *pmdp, unsigned long addr, unsigned long end, |
| phys_addr_t phys, pgprot_t prot) |
| { |
| pte_t *ptep; |
| |
| ptep = pte_set_fixmap_offset(pmdp, addr); |
| do { |
| pte_t old_pte = READ_ONCE(*ptep); |
| |
| set_pte(ptep, pfn_pte(__phys_to_pfn(phys), prot)); |
| |
| /* |
| * After the PTE entry has been populated once, we |
| * only allow updates to the permission attributes. |
| */ |
| BUG_ON(!pgattr_change_is_safe(pte_val(old_pte), |
| READ_ONCE(pte_val(*ptep)))); |
| |
| phys += PAGE_SIZE; |
| } while (ptep++, addr += PAGE_SIZE, addr != end); |
| |
| pte_clear_fixmap(); |
| } |
| |
| static void alloc_init_cont_pte(pmd_t *pmdp, unsigned long addr, |
| unsigned long end, phys_addr_t phys, |
| pgprot_t prot, |
| phys_addr_t (*pgtable_alloc)(void), |
| int flags) |
| { |
| unsigned long next; |
| pmd_t pmd = READ_ONCE(*pmdp); |
| |
| BUG_ON(pmd_sect(pmd)); |
| if (pmd_none(pmd)) { |
| phys_addr_t pte_phys; |
| BUG_ON(!pgtable_alloc); |
| pte_phys = pgtable_alloc(); |
| __pmd_populate(pmdp, pte_phys, PMD_TYPE_TABLE); |
| pmd = READ_ONCE(*pmdp); |
| } |
| BUG_ON(pmd_bad(pmd)); |
| |
| do { |
| pgprot_t __prot = prot; |
| |
| next = pte_cont_addr_end(addr, end); |
| |
| /* use a contiguous mapping if the range is suitably aligned */ |
| if ((((addr | next | phys) & ~CONT_PTE_MASK) == 0) && |
| (flags & NO_CONT_MAPPINGS) == 0) |
| __prot = __pgprot(pgprot_val(prot) | PTE_CONT); |
| |
| init_pte(pmdp, addr, next, phys, __prot); |
| |
| phys += next - addr; |
| } while (addr = next, addr != end); |
| } |
| |
| static void init_pmd(pud_t *pudp, unsigned long addr, unsigned long end, |
| phys_addr_t phys, pgprot_t prot, |
| phys_addr_t (*pgtable_alloc)(void), int flags) |
| { |
| unsigned long next; |
| pmd_t *pmdp; |
| |
| pmdp = pmd_set_fixmap_offset(pudp, addr); |
| do { |
| pmd_t old_pmd = READ_ONCE(*pmdp); |
| |
| next = pmd_addr_end(addr, end); |
| |
| /* try section mapping first */ |
| if (((addr | next | phys) & ~SECTION_MASK) == 0 && |
| (flags & NO_BLOCK_MAPPINGS) == 0) { |
| pmd_set_huge(pmdp, phys, prot); |
| |
| /* |
| * After the PMD entry has been populated once, we |
| * only allow updates to the permission attributes. |
| */ |
| BUG_ON(!pgattr_change_is_safe(pmd_val(old_pmd), |
| READ_ONCE(pmd_val(*pmdp)))); |
| } else { |
| alloc_init_cont_pte(pmdp, addr, next, phys, prot, |
| pgtable_alloc, flags); |
| |
| BUG_ON(pmd_val(old_pmd) != 0 && |
| pmd_val(old_pmd) != READ_ONCE(pmd_val(*pmdp))); |
| } |
| phys += next - addr; |
| } while (pmdp++, addr = next, addr != end); |
| |
| pmd_clear_fixmap(); |
| } |
| |
| static void alloc_init_cont_pmd(pud_t *pudp, unsigned long addr, |
| unsigned long end, phys_addr_t phys, |
| pgprot_t prot, |
| phys_addr_t (*pgtable_alloc)(void), int flags) |
| { |
| unsigned long next; |
| pud_t pud = READ_ONCE(*pudp); |
| |
| /* |
| * Check for initial section mappings in the pgd/pud. |
| */ |
| BUG_ON(pud_sect(pud)); |
| if (pud_none(pud)) { |
| phys_addr_t pmd_phys; |
| BUG_ON(!pgtable_alloc); |
| pmd_phys = pgtable_alloc(); |
| __pud_populate(pudp, pmd_phys, PUD_TYPE_TABLE); |
| pud = READ_ONCE(*pudp); |
| } |
| BUG_ON(pud_bad(pud)); |
| |
| do { |
| pgprot_t __prot = prot; |
| |
| next = pmd_cont_addr_end(addr, end); |
| |
| /* use a contiguous mapping if the range is suitably aligned */ |
| if ((((addr | next | phys) & ~CONT_PMD_MASK) == 0) && |
| (flags & NO_CONT_MAPPINGS) == 0) |
| __prot = __pgprot(pgprot_val(prot) | PTE_CONT); |
| |
| init_pmd(pudp, addr, next, phys, __prot, pgtable_alloc, flags); |
| |
| phys += next - addr; |
| } while (addr = next, addr != end); |
| } |
| |
| static inline bool use_1G_block(unsigned long addr, unsigned long next, |
| unsigned long phys) |
| { |
| if (PAGE_SHIFT != 12) |
| return false; |
| |
| if (((addr | next | phys) & ~PUD_MASK) != 0) |
| return false; |
| |
| return true; |
| } |
| |
| static void alloc_init_pud(pgd_t *pgdp, unsigned long addr, unsigned long end, |
| phys_addr_t phys, pgprot_t prot, |
| phys_addr_t (*pgtable_alloc)(void), |
| int flags) |
| { |
| unsigned long next; |
| pud_t *pudp; |
| pgd_t pgd = READ_ONCE(*pgdp); |
| |
| if (pgd_none(pgd)) { |
| phys_addr_t pud_phys; |
| BUG_ON(!pgtable_alloc); |
| pud_phys = pgtable_alloc(); |
| __pgd_populate(pgdp, pud_phys, PUD_TYPE_TABLE); |
| pgd = READ_ONCE(*pgdp); |
| } |
| BUG_ON(pgd_bad(pgd)); |
| |
| pudp = pud_set_fixmap_offset(pgdp, addr); |
| do { |
| pud_t old_pud = READ_ONCE(*pudp); |
| |
| next = pud_addr_end(addr, end); |
| |
| /* |
| * For 4K granule only, attempt to put down a 1GB block |
| */ |
| if (use_1G_block(addr, next, phys) && |
| (flags & NO_BLOCK_MAPPINGS) == 0) { |
| pud_set_huge(pudp, phys, prot); |
| |
| /* |
| * After the PUD entry has been populated once, we |
| * only allow updates to the permission attributes. |
| */ |
| BUG_ON(!pgattr_change_is_safe(pud_val(old_pud), |
| READ_ONCE(pud_val(*pudp)))); |
| } else { |
| alloc_init_cont_pmd(pudp, addr, next, phys, prot, |
| pgtable_alloc, flags); |
| |
| BUG_ON(pud_val(old_pud) != 0 && |
| pud_val(old_pud) != READ_ONCE(pud_val(*pudp))); |
| } |
| phys += next - addr; |
| } while (pudp++, addr = next, addr != end); |
| |
| pud_clear_fixmap(); |
| } |
| |
| static void __create_pgd_mapping(pgd_t *pgdir, phys_addr_t phys, |
| unsigned long virt, phys_addr_t size, |
| pgprot_t prot, |
| phys_addr_t (*pgtable_alloc)(void), |
| int flags) |
| { |
| unsigned long addr, length, end, next; |
| pgd_t *pgdp = pgd_offset_raw(pgdir, virt); |
| |
| /* |
| * If the virtual and physical address don't have the same offset |
| * within a page, we cannot map the region as the caller expects. |
| */ |
| if (WARN_ON((phys ^ virt) & ~PAGE_MASK)) |
| return; |
| |
| phys &= PAGE_MASK; |
| addr = virt & PAGE_MASK; |
| length = PAGE_ALIGN(size + (virt & ~PAGE_MASK)); |
| |
| end = addr + length; |
| do { |
| next = pgd_addr_end(addr, end); |
| alloc_init_pud(pgdp, addr, next, phys, prot, pgtable_alloc, |
| flags); |
| phys += next - addr; |
| } while (pgdp++, addr = next, addr != end); |
| } |
| |
| static phys_addr_t pgd_pgtable_alloc(void) |
| { |
| void *ptr = (void *)__get_free_page(PGALLOC_GFP); |
| if (!ptr || !pgtable_page_ctor(virt_to_page(ptr))) |
| BUG(); |
| |
| /* Ensure the zeroed page is visible to the page table walker */ |
| dsb(ishst); |
| return __pa(ptr); |
| } |
| |
| /* |
| * This function can only be used to modify existing table entries, |
| * without allocating new levels of table. Note that this permits the |
| * creation of new section or page entries. |
| */ |
| static void __init create_mapping_noalloc(phys_addr_t phys, unsigned long virt, |
| phys_addr_t size, pgprot_t prot) |
| { |
| if (virt < VMALLOC_START) { |
| pr_warn("BUG: not creating mapping for %pa at 0x%016lx - outside kernel range\n", |
| &phys, virt); |
| return; |
| } |
| __create_pgd_mapping(init_mm.pgd, phys, virt, size, prot, NULL, |
| NO_CONT_MAPPINGS); |
| } |
| |
| void __init create_pgd_mapping(struct mm_struct *mm, phys_addr_t phys, |
| unsigned long virt, phys_addr_t size, |
| pgprot_t prot, bool page_mappings_only) |
| { |
| int flags = 0; |
| |
| BUG_ON(mm == &init_mm); |
| |
| if (page_mappings_only) |
| flags = NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS; |
| |
| __create_pgd_mapping(mm->pgd, phys, virt, size, prot, |
| pgd_pgtable_alloc, flags); |
| } |
| |
| static void update_mapping_prot(phys_addr_t phys, unsigned long virt, |
| phys_addr_t size, pgprot_t prot) |
| { |
| if (virt < VMALLOC_START) { |
| pr_warn("BUG: not updating mapping for %pa at 0x%016lx - outside kernel range\n", |
| &phys, virt); |
| return; |
| } |
| |
| __create_pgd_mapping(init_mm.pgd, phys, virt, size, prot, NULL, |
| NO_CONT_MAPPINGS); |
| |
| /* flush the TLBs after updating live kernel mappings */ |
| flush_tlb_kernel_range(virt, virt + size); |
| } |
| |
| static void __init __map_memblock(pgd_t *pgdp, phys_addr_t start, |
| phys_addr_t end, pgprot_t prot, int flags) |
| { |
| __create_pgd_mapping(pgdp, start, __phys_to_virt(start), end - start, |
| prot, early_pgtable_alloc, flags); |
| } |
| |
| void __init mark_linear_text_alias_ro(void) |
| { |
| /* |
| * Remove the write permissions from the linear alias of .text/.rodata |
| */ |
| update_mapping_prot(__pa_symbol(_text), (unsigned long)lm_alias(_text), |
| (unsigned long)__init_begin - (unsigned long)_text, |
| PAGE_KERNEL_RO); |
| } |
| |
| static void __init map_mem(pgd_t *pgdp) |
| { |
| phys_addr_t kernel_start = __pa_symbol(_text); |
| phys_addr_t kernel_end = __pa_symbol(__init_begin); |
| struct memblock_region *reg; |
| int flags = 0; |
| |
| if (debug_pagealloc_enabled()) |
| flags = NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS; |
| |
| /* |
| * Take care not to create a writable alias for the |
| * read-only text and rodata sections of the kernel image. |
| * So temporarily mark them as NOMAP to skip mappings in |
| * the following for-loop |
| */ |
| memblock_mark_nomap(kernel_start, kernel_end - kernel_start); |
| #ifdef CONFIG_KEXEC_CORE |
| if (crashk_res.end) |
| memblock_mark_nomap(crashk_res.start, |
| resource_size(&crashk_res)); |
| #endif |
| |
| /* 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; |
| if (memblock_is_nomap(reg)) |
| continue; |
| |
| __map_memblock(pgdp, start, end, PAGE_KERNEL, flags); |
| } |
| |
| /* |
| * Map the linear alias of the [_text, __init_begin) interval |
| * as non-executable now, and remove the write permission in |
| * mark_linear_text_alias_ro() below (which will be called after |
| * alternative patching has completed). This makes the contents |
| * of the region accessible to subsystems such as hibernate, |
| * but protects it from inadvertent modification or execution. |
| * Note that contiguous mappings cannot be remapped in this way, |
| * so we should avoid them here. |
| */ |
| __map_memblock(pgdp, kernel_start, kernel_end, |
| PAGE_KERNEL, NO_CONT_MAPPINGS); |
| memblock_clear_nomap(kernel_start, kernel_end - kernel_start); |
| |
| #ifdef CONFIG_KEXEC_CORE |
| /* |
| * Use page-level mappings here so that we can shrink the region |
| * in page granularity and put back unused memory to buddy system |
| * through /sys/kernel/kexec_crash_size interface. |
| */ |
| if (crashk_res.end) { |
| __map_memblock(pgdp, crashk_res.start, crashk_res.end + 1, |
| PAGE_KERNEL, |
| NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS); |
| memblock_clear_nomap(crashk_res.start, |
| resource_size(&crashk_res)); |
| } |
| #endif |
| } |
| |
| void mark_rodata_ro(void) |
| { |
| unsigned long section_size; |
| |
| /* |
| * mark .rodata as read only. Use __init_begin rather than __end_rodata |
| * to cover NOTES and EXCEPTION_TABLE. |
| */ |
| section_size = (unsigned long)__init_begin - (unsigned long)__start_rodata; |
| update_mapping_prot(__pa_symbol(__start_rodata), (unsigned long)__start_rodata, |
| section_size, PAGE_KERNEL_RO); |
| |
| debug_checkwx(); |
| } |
| |
| static void __init map_kernel_segment(pgd_t *pgdp, void *va_start, void *va_end, |
| pgprot_t prot, struct vm_struct *vma, |
| int flags, unsigned long vm_flags) |
| { |
| phys_addr_t pa_start = __pa_symbol(va_start); |
| unsigned long size = va_end - va_start; |
| |
| BUG_ON(!PAGE_ALIGNED(pa_start)); |
| BUG_ON(!PAGE_ALIGNED(size)); |
| |
| __create_pgd_mapping(pgdp, pa_start, (unsigned long)va_start, size, prot, |
| early_pgtable_alloc, flags); |
| |
| if (!(vm_flags & VM_NO_GUARD)) |
| size += PAGE_SIZE; |
| |
| vma->addr = va_start; |
| vma->phys_addr = pa_start; |
| vma->size = size; |
| vma->flags = VM_MAP | vm_flags; |
| vma->caller = __builtin_return_address(0); |
| |
| vm_area_add_early(vma); |
| } |
| |
| static int __init parse_rodata(char *arg) |
| { |
| return strtobool(arg, &rodata_enabled); |
| } |
| early_param("rodata", parse_rodata); |
| |
| #ifdef CONFIG_UNMAP_KERNEL_AT_EL0 |
| static int __init map_entry_trampoline(void) |
| { |
| pgprot_t prot = rodata_enabled ? PAGE_KERNEL_ROX : PAGE_KERNEL_EXEC; |
| phys_addr_t pa_start = __pa_symbol(__entry_tramp_text_start); |
| |
| /* The trampoline is always mapped and can therefore be global */ |
| pgprot_val(prot) &= ~PTE_NG; |
| |
| /* Map only the text into the trampoline page table */ |
| memset(tramp_pg_dir, 0, PGD_SIZE); |
| __create_pgd_mapping(tramp_pg_dir, pa_start, TRAMP_VALIAS, PAGE_SIZE, |
| prot, pgd_pgtable_alloc, 0); |
| |
| /* Map both the text and data into the kernel page table */ |
| __set_fixmap(FIX_ENTRY_TRAMP_TEXT, pa_start, prot); |
| if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) { |
| extern char __entry_tramp_data_start[]; |
| |
| __set_fixmap(FIX_ENTRY_TRAMP_DATA, |
| __pa_symbol(__entry_tramp_data_start), |
| PAGE_KERNEL_RO); |
| } |
| |
| return 0; |
| } |
| core_initcall(map_entry_trampoline); |
| #endif |
| |
| /* |
| * Create fine-grained mappings for the kernel. |
| */ |
| static void __init map_kernel(pgd_t *pgdp) |
| { |
| static struct vm_struct vmlinux_text, vmlinux_rodata, vmlinux_inittext, |
| vmlinux_initdata, vmlinux_data; |
| |
| /* |
| * External debuggers may need to write directly to the text |
| * mapping to install SW breakpoints. Allow this (only) when |
| * explicitly requested with rodata=off. |
| */ |
| pgprot_t text_prot = rodata_enabled ? PAGE_KERNEL_ROX : PAGE_KERNEL_EXEC; |
| |
| /* |
| * Only rodata will be remapped with different permissions later on, |
| * all other segments are allowed to use contiguous mappings. |
| */ |
| map_kernel_segment(pgdp, _text, _etext, text_prot, &vmlinux_text, 0, |
| VM_NO_GUARD); |
| map_kernel_segment(pgdp, __start_rodata, __inittext_begin, PAGE_KERNEL, |
| &vmlinux_rodata, NO_CONT_MAPPINGS, VM_NO_GUARD); |
| map_kernel_segment(pgdp, __inittext_begin, __inittext_end, text_prot, |
| &vmlinux_inittext, 0, VM_NO_GUARD); |
| map_kernel_segment(pgdp, __initdata_begin, __initdata_end, PAGE_KERNEL, |
| &vmlinux_initdata, 0, VM_NO_GUARD); |
| map_kernel_segment(pgdp, _data, _end, PAGE_KERNEL, &vmlinux_data, 0, 0); |
| |
| if (!READ_ONCE(pgd_val(*pgd_offset_raw(pgdp, FIXADDR_START)))) { |
| /* |
| * The fixmap falls in a separate pgd to the kernel, and doesn't |
| * live in the carveout for the swapper_pg_dir. We can simply |
| * re-use the existing dir for the fixmap. |
| */ |
| set_pgd(pgd_offset_raw(pgdp, FIXADDR_START), |
| READ_ONCE(*pgd_offset_k(FIXADDR_START))); |
| } else if (CONFIG_PGTABLE_LEVELS > 3) { |
| /* |
| * The fixmap shares its top level pgd entry with the kernel |
| * mapping. This can really only occur when we are running |
| * with 16k/4 levels, so we can simply reuse the pud level |
| * entry instead. |
| */ |
| BUG_ON(!IS_ENABLED(CONFIG_ARM64_16K_PAGES)); |
| pud_populate(&init_mm, |
| pud_set_fixmap_offset(pgdp, FIXADDR_START), |
| lm_alias(bm_pmd)); |
| pud_clear_fixmap(); |
| } else { |
| BUG(); |
| } |
| |
| kasan_copy_shadow(pgdp); |
| } |
| |
| /* |
| * paging_init() sets up the page tables, initialises the zone memory |
| * maps and sets up the zero page. |
| */ |
| void __init paging_init(void) |
| { |
| phys_addr_t pgd_phys = early_pgtable_alloc(); |
| pgd_t *pgdp = pgd_set_fixmap(pgd_phys); |
| |
| map_kernel(pgdp); |
| map_mem(pgdp); |
| |
| /* |
| * We want to reuse the original swapper_pg_dir so we don't have to |
| * communicate the new address to non-coherent secondaries in |
| * secondary_entry, and so cpu_switch_mm can generate the address with |
| * adrp+add rather than a load from some global variable. |
| * |
| * To do this we need to go via a temporary pgd. |
| */ |
| cpu_replace_ttbr1(__va(pgd_phys)); |
| memcpy(swapper_pg_dir, pgdp, PGD_SIZE); |
| cpu_replace_ttbr1(lm_alias(swapper_pg_dir)); |
| |
| pgd_clear_fixmap(); |
| memblock_free(pgd_phys, PAGE_SIZE); |
| |
| /* |
| * We only reuse the PGD from the swapper_pg_dir, not the pud + pmd |
| * allocated with it. |
| */ |
| memblock_free(__pa_symbol(swapper_pg_dir) + PAGE_SIZE, |
| __pa_symbol(swapper_pg_end) - __pa_symbol(swapper_pg_dir) |
| - PAGE_SIZE); |
| } |
| |
| /* |
| * Check whether a kernel address is valid (derived from arch/x86/). |
| */ |
| int kern_addr_valid(unsigned long addr) |
| { |
| pgd_t *pgdp; |
| pud_t *pudp, pud; |
| pmd_t *pmdp, pmd; |
| pte_t *ptep, pte; |
| |
| if ((((long)addr) >> VA_BITS) != -1UL) |
| return 0; |
| |
| pgdp = pgd_offset_k(addr); |
| if (pgd_none(READ_ONCE(*pgdp))) |
| return 0; |
| |
| pudp = pud_offset(pgdp, addr); |
| pud = READ_ONCE(*pudp); |
| if (pud_none(pud)) |
| return 0; |
| |
| if (pud_sect(pud)) |
| return pfn_valid(pud_pfn(pud)); |
| |
| pmdp = pmd_offset(pudp, addr); |
| pmd = READ_ONCE(*pmdp); |
| if (pmd_none(pmd)) |
| return 0; |
| |
| if (pmd_sect(pmd)) |
| return pfn_valid(pmd_pfn(pmd)); |
| |
| ptep = pte_offset_kernel(pmdp, addr); |
| pte = READ_ONCE(*ptep); |
| if (pte_none(pte)) |
| return 0; |
| |
| return pfn_valid(pte_pfn(pte)); |
| } |
| #ifdef CONFIG_SPARSEMEM_VMEMMAP |
| #if !ARM64_SWAPPER_USES_SECTION_MAPS |
| int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, |
| struct vmem_altmap *altmap) |
| { |
| return vmemmap_populate_basepages(start, end, node); |
| } |
| #else /* !ARM64_SWAPPER_USES_SECTION_MAPS */ |
| int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, |
| struct vmem_altmap *altmap) |
| { |
| unsigned long addr = start; |
| unsigned long next; |
| pgd_t *pgdp; |
| pud_t *pudp; |
| pmd_t *pmdp; |
| |
| do { |
| next = pmd_addr_end(addr, end); |
| |
| pgdp = vmemmap_pgd_populate(addr, node); |
| if (!pgdp) |
| return -ENOMEM; |
| |
| pudp = vmemmap_pud_populate(pgdp, addr, node); |
| if (!pudp) |
| return -ENOMEM; |
| |
| pmdp = pmd_offset(pudp, addr); |
| if (pmd_none(READ_ONCE(*pmdp))) { |
| void *p = NULL; |
| |
| p = vmemmap_alloc_block_buf(PMD_SIZE, node); |
| if (!p) |
| return -ENOMEM; |
| |
| pmd_set_huge(pmdp, __pa(p), __pgprot(PROT_SECT_NORMAL)); |
| } else |
| vmemmap_verify((pte_t *)pmdp, node, addr, next); |
| } while (addr = next, addr != end); |
| |
| return 0; |
| } |
| #endif /* CONFIG_ARM64_64K_PAGES */ |
| void vmemmap_free(unsigned long start, unsigned long end, |
| struct vmem_altmap *altmap) |
| { |
| } |
| #endif /* CONFIG_SPARSEMEM_VMEMMAP */ |
| |
| static inline pud_t * fixmap_pud(unsigned long addr) |
| { |
| pgd_t *pgdp = pgd_offset_k(addr); |
| pgd_t pgd = READ_ONCE(*pgdp); |
| |
| BUG_ON(pgd_none(pgd) || pgd_bad(pgd)); |
| |
| return pud_offset_kimg(pgdp, addr); |
| } |
| |
| static inline pmd_t * fixmap_pmd(unsigned long addr) |
| { |
| pud_t *pudp = fixmap_pud(addr); |
| pud_t pud = READ_ONCE(*pudp); |
| |
| BUG_ON(pud_none(pud) || pud_bad(pud)); |
| |
| return pmd_offset_kimg(pudp, addr); |
| } |
| |
| static inline pte_t * fixmap_pte(unsigned long addr) |
| { |
| return &bm_pte[pte_index(addr)]; |
| } |
| |
| /* |
| * The p*d_populate functions call virt_to_phys implicitly so they can't be used |
| * directly on kernel symbols (bm_p*d). This function is called too early to use |
| * lm_alias so __p*d_populate functions must be used to populate with the |
| * physical address from __pa_symbol. |
| */ |
| void __init early_fixmap_init(void) |
| { |
| pgd_t *pgdp, pgd; |
| pud_t *pudp; |
| pmd_t *pmdp; |
| unsigned long addr = FIXADDR_START; |
| |
| pgdp = pgd_offset_k(addr); |
| pgd = READ_ONCE(*pgdp); |
| if (CONFIG_PGTABLE_LEVELS > 3 && |
| !(pgd_none(pgd) || pgd_page_paddr(pgd) == __pa_symbol(bm_pud))) { |
| /* |
| * We only end up here if the kernel mapping and the fixmap |
| * share the top level pgd entry, which should only happen on |
| * 16k/4 levels configurations. |
| */ |
| BUG_ON(!IS_ENABLED(CONFIG_ARM64_16K_PAGES)); |
| pudp = pud_offset_kimg(pgdp, addr); |
| } else { |
| if (pgd_none(pgd)) |
| __pgd_populate(pgdp, __pa_symbol(bm_pud), PUD_TYPE_TABLE); |
| pudp = fixmap_pud(addr); |
| } |
| if (pud_none(READ_ONCE(*pudp))) |
| __pud_populate(pudp, __pa_symbol(bm_pmd), PMD_TYPE_TABLE); |
| pmdp = fixmap_pmd(addr); |
| __pmd_populate(pmdp, __pa_symbol(bm_pte), PMD_TYPE_TABLE); |
| |
| /* |
| * The boot-ioremap range spans multiple pmds, for which |
| * we are not prepared: |
| */ |
| BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT) |
| != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT)); |
| |
| if ((pmdp != fixmap_pmd(fix_to_virt(FIX_BTMAP_BEGIN))) |
| || pmdp != fixmap_pmd(fix_to_virt(FIX_BTMAP_END))) { |
| WARN_ON(1); |
| pr_warn("pmdp %p != %p, %p\n", |
| pmdp, fixmap_pmd(fix_to_virt(FIX_BTMAP_BEGIN)), |
| fixmap_pmd(fix_to_virt(FIX_BTMAP_END))); |
| 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); |
| } |
| } |
| |
| /* |
| * Unusually, this is also called in IRQ context (ghes_iounmap_irq) so if we |
| * ever need to use IPIs for TLB broadcasting, then we're in trouble here. |
| */ |
| void __set_fixmap(enum fixed_addresses idx, |
| phys_addr_t phys, pgprot_t flags) |
| { |
| unsigned long addr = __fix_to_virt(idx); |
| pte_t *ptep; |
| |
| BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses); |
| |
| ptep = fixmap_pte(addr); |
| |
| if (pgprot_val(flags)) { |
| set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, flags)); |
| } else { |
| pte_clear(&init_mm, addr, ptep); |
| flush_tlb_kernel_range(addr, addr+PAGE_SIZE); |
| } |
| } |
| |
| void *__init __fixmap_remap_fdt(phys_addr_t dt_phys, int *size, pgprot_t prot) |
| { |
| const u64 dt_virt_base = __fix_to_virt(FIX_FDT); |
| int offset; |
| void *dt_virt; |
| |
| /* |
| * Check whether the physical FDT address is set and meets the minimum |
| * alignment requirement. Since we are relying on MIN_FDT_ALIGN to be |
| * at least 8 bytes so that we can always access the magic and size |
| * fields of the FDT header after mapping the first chunk, double check |
| * here if that is indeed the case. |
| */ |
| BUILD_BUG_ON(MIN_FDT_ALIGN < 8); |
| if (!dt_phys || dt_phys % MIN_FDT_ALIGN) |
| return NULL; |
| |
| /* |
| * Make sure that the FDT region can be mapped without the need to |
| * allocate additional translation table pages, so that it is safe |
| * to call create_mapping_noalloc() this early. |
| * |
| * On 64k pages, the FDT will be mapped using PTEs, so we need to |
| * be in the same PMD as the rest of the fixmap. |
| * On 4k pages, we'll use section mappings for the FDT so we only |
| * have to be in the same PUD. |
| */ |
| BUILD_BUG_ON(dt_virt_base % SZ_2M); |
| |
| BUILD_BUG_ON(__fix_to_virt(FIX_FDT_END) >> SWAPPER_TABLE_SHIFT != |
| __fix_to_virt(FIX_BTMAP_BEGIN) >> SWAPPER_TABLE_SHIFT); |
| |
| offset = dt_phys % SWAPPER_BLOCK_SIZE; |
| dt_virt = (void *)dt_virt_base + offset; |
| |
| /* map the first chunk so we can read the size from the header */ |
| create_mapping_noalloc(round_down(dt_phys, SWAPPER_BLOCK_SIZE), |
| dt_virt_base, SWAPPER_BLOCK_SIZE, prot); |
| |
| if (fdt_magic(dt_virt) != FDT_MAGIC) |
| return NULL; |
| |
| *size = fdt_totalsize(dt_virt); |
| if (*size > MAX_FDT_SIZE) |
| return NULL; |
| |
| if (offset + *size > SWAPPER_BLOCK_SIZE) |
| create_mapping_noalloc(round_down(dt_phys, SWAPPER_BLOCK_SIZE), dt_virt_base, |
| round_up(offset + *size, SWAPPER_BLOCK_SIZE), prot); |
| |
| return dt_virt; |
| } |
| |
| void *__init fixmap_remap_fdt(phys_addr_t dt_phys) |
| { |
| void *dt_virt; |
| int size; |
| |
| dt_virt = __fixmap_remap_fdt(dt_phys, &size, PAGE_KERNEL_RO); |
| if (!dt_virt) |
| return NULL; |
| |
| memblock_reserve(dt_phys, size); |
| return dt_virt; |
| } |
| |
| int __init arch_ioremap_pud_supported(void) |
| { |
| /* only 4k granule supports level 1 block mappings */ |
| return IS_ENABLED(CONFIG_ARM64_4K_PAGES); |
| } |
| |
| int __init arch_ioremap_pmd_supported(void) |
| { |
| return 1; |
| } |
| |
| int pud_set_huge(pud_t *pudp, phys_addr_t phys, pgprot_t prot) |
| { |
| pgprot_t sect_prot = __pgprot(PUD_TYPE_SECT | |
| pgprot_val(mk_sect_prot(prot))); |
| |
| /* ioremap_page_range doesn't honour BBM */ |
| if (pud_present(READ_ONCE(*pudp))) |
| return 0; |
| |
| BUG_ON(phys & ~PUD_MASK); |
| set_pud(pudp, pfn_pud(__phys_to_pfn(phys), sect_prot)); |
| return 1; |
| } |
| |
| int pmd_set_huge(pmd_t *pmdp, phys_addr_t phys, pgprot_t prot) |
| { |
| pgprot_t sect_prot = __pgprot(PMD_TYPE_SECT | |
| pgprot_val(mk_sect_prot(prot))); |
| |
| /* ioremap_page_range doesn't honour BBM */ |
| if (pmd_present(READ_ONCE(*pmdp))) |
| return 0; |
| |
| BUG_ON(phys & ~PMD_MASK); |
| set_pmd(pmdp, pfn_pmd(__phys_to_pfn(phys), sect_prot)); |
| return 1; |
| } |
| |
| int pud_clear_huge(pud_t *pudp) |
| { |
| if (!pud_sect(READ_ONCE(*pudp))) |
| return 0; |
| pud_clear(pudp); |
| return 1; |
| } |
| |
| int pmd_clear_huge(pmd_t *pmdp) |
| { |
| if (!pmd_sect(READ_ONCE(*pmdp))) |
| return 0; |
| pmd_clear(pmdp); |
| return 1; |
| } |