// SPDX-License-Identifier: GPL-2.0-only /* * linux/arch/x86_64/mm/init.c * * Copyright (C) 1995 Linus Torvalds * Copyright (C) 2000 Pavel Machek * Copyright (C) 2002,2003 Andi Kleen */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "mm_internal.h" #include "ident_map.c" #define DEFINE_POPULATE(fname, type1, type2, init) \ static inline void fname##_init(struct mm_struct *mm, \ type1##_t *arg1, type2##_t *arg2, bool init) \ { \ if (init) \ fname##_safe(mm, arg1, arg2); \ else \ fname(mm, arg1, arg2); \ } DEFINE_POPULATE(p4d_populate, p4d, pud, init) DEFINE_POPULATE(pgd_populate, pgd, p4d, init) DEFINE_POPULATE(pud_populate, pud, pmd, init) DEFINE_POPULATE(pmd_populate_kernel, pmd, pte, init) #define DEFINE_ENTRY(type1, type2, init) \ static inline void set_##type1##_init(type1##_t *arg1, \ type2##_t arg2, bool init) \ { \ if (init) \ set_##type1##_safe(arg1, arg2); \ else \ set_##type1(arg1, arg2); \ } DEFINE_ENTRY(p4d, p4d, init) DEFINE_ENTRY(pud, pud, init) DEFINE_ENTRY(pmd, pmd, init) DEFINE_ENTRY(pte, pte, init) static inline pgprot_t prot_sethuge(pgprot_t prot) { WARN_ON_ONCE(pgprot_val(prot) & _PAGE_PAT); return __pgprot(pgprot_val(prot) | _PAGE_PSE); } /* * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the * physical space so we can cache the place of the first one and move * around without checking the pgd every time. */ /* Bits supported by the hardware: */ pteval_t __supported_pte_mask __read_mostly = ~0; /* Bits allowed in normal kernel mappings: */ pteval_t __default_kernel_pte_mask __read_mostly = ~0; EXPORT_SYMBOL_GPL(__supported_pte_mask); /* Used in PAGE_KERNEL_* macros which are reasonably used out-of-tree: */ EXPORT_SYMBOL(__default_kernel_pte_mask); int force_personality32; /* * noexec32=on|off * Control non executable heap for 32bit processes. * * on PROT_READ does not imply PROT_EXEC for 32-bit processes (default) * off PROT_READ implies PROT_EXEC */ static int __init nonx32_setup(char *str) { if (!strcmp(str, "on")) force_personality32 &= ~READ_IMPLIES_EXEC; else if (!strcmp(str, "off")) force_personality32 |= READ_IMPLIES_EXEC; return 1; } __setup("noexec32=", nonx32_setup); static void sync_global_pgds_l5(unsigned long start, unsigned long end) { unsigned long addr; for (addr = start; addr <= end; addr = ALIGN(addr + 1, PGDIR_SIZE)) { const pgd_t *pgd_ref = pgd_offset_k(addr); struct page *page; /* Check for overflow */ if (addr < start) break; if (pgd_none(*pgd_ref)) continue; spin_lock(&pgd_lock); list_for_each_entry(page, &pgd_list, lru) { pgd_t *pgd; spinlock_t *pgt_lock; pgd = (pgd_t *)page_address(page) + pgd_index(addr); /* the pgt_lock only for Xen */ pgt_lock = &pgd_page_get_mm(page)->page_table_lock; spin_lock(pgt_lock); if (!pgd_none(*pgd_ref) && !pgd_none(*pgd)) BUG_ON(pgd_page_vaddr(*pgd) != pgd_page_vaddr(*pgd_ref)); if (pgd_none(*pgd)) set_pgd(pgd, *pgd_ref); spin_unlock(pgt_lock); } spin_unlock(&pgd_lock); } } static void sync_global_pgds_l4(unsigned long start, unsigned long end) { unsigned long addr; for (addr = start; addr <= end; addr = ALIGN(addr + 1, PGDIR_SIZE)) { pgd_t *pgd_ref = pgd_offset_k(addr); const p4d_t *p4d_ref; struct page *page; /* * With folded p4d, pgd_none() is always false, we need to * handle synchronization on p4d level. */ MAYBE_BUILD_BUG_ON(pgd_none(*pgd_ref)); p4d_ref = p4d_offset(pgd_ref, addr); if (p4d_none(*p4d_ref)) continue; spin_lock(&pgd_lock); list_for_each_entry(page, &pgd_list, lru) { pgd_t *pgd; p4d_t *p4d; spinlock_t *pgt_lock; pgd = (pgd_t *)page_address(page) + pgd_index(addr); p4d = p4d_offset(pgd, addr); /* the pgt_lock only for Xen */ pgt_lock = &pgd_page_get_mm(page)->page_table_lock; spin_lock(pgt_lock); if (!p4d_none(*p4d_ref) && !p4d_none(*p4d)) BUG_ON(p4d_pgtable(*p4d) != p4d_pgtable(*p4d_ref)); if (p4d_none(*p4d)) set_p4d(p4d, *p4d_ref); spin_unlock(pgt_lock); } spin_unlock(&pgd_lock); } } /* * When memory was added make sure all the processes MM have * suitable PGD entries in the local PGD level page. */ static void sync_global_pgds(unsigned long start, unsigned long end) { if (pgtable_l5_enabled()) sync_global_pgds_l5(start, end); else sync_global_pgds_l4(start, end); } /* * NOTE: This function is marked __ref because it calls __init function * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0. */ static __ref void *spp_getpage(void) { void *ptr; if (after_bootmem) ptr = (void *) get_zeroed_page(GFP_ATOMIC); else ptr = memblock_alloc(PAGE_SIZE, PAGE_SIZE); if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) { panic("set_pte_phys: cannot allocate page data %s\n", after_bootmem ? "after bootmem" : ""); } pr_debug("spp_getpage %p\n", ptr); return ptr; } static p4d_t *fill_p4d(pgd_t *pgd, unsigned long vaddr) { if (pgd_none(*pgd)) { p4d_t *p4d = (p4d_t *)spp_getpage(); pgd_populate(&init_mm, pgd, p4d); if (p4d != p4d_offset(pgd, 0)) printk(KERN_ERR "PAGETABLE BUG #00! %p <-> %p\n", p4d, p4d_offset(pgd, 0)); } return p4d_offset(pgd, vaddr); } static pud_t *fill_pud(p4d_t *p4d, unsigned long vaddr) { if (p4d_none(*p4d)) { pud_t *pud = (pud_t *)spp_getpage(); p4d_populate(&init_mm, p4d, pud); if (pud != pud_offset(p4d, 0)) printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n", pud, pud_offset(p4d, 0)); } return pud_offset(p4d, vaddr); } static pmd_t *fill_pmd(pud_t *pud, unsigned long vaddr) { if (pud_none(*pud)) { pmd_t *pmd = (pmd_t *) spp_getpage(); pud_populate(&init_mm, pud, pmd); if (pmd != pmd_offset(pud, 0)) printk(KERN_ERR "PAGETABLE BUG #02! %p <-> %p\n", pmd, pmd_offset(pud, 0)); } return pmd_offset(pud, vaddr); } static pte_t *fill_pte(pmd_t *pmd, unsigned long vaddr) { if (pmd_none(*pmd)) { pte_t *pte = (pte_t *) spp_getpage(); pmd_populate_kernel(&init_mm, pmd, pte); if (pte != pte_offset_kernel(pmd, 0)) printk(KERN_ERR "PAGETABLE BUG #03!\n"); } return pte_offset_kernel(pmd, vaddr); } static void __set_pte_vaddr(pud_t *pud, unsigned long vaddr, pte_t new_pte) { pmd_t *pmd = fill_pmd(pud, vaddr); pte_t *pte = fill_pte(pmd, vaddr); set_pte(pte, new_pte); /* * It's enough to flush this one mapping. * (PGE mappings get flushed as well) */ flush_tlb_one_kernel(vaddr); } void set_pte_vaddr_p4d(p4d_t *p4d_page, unsigned long vaddr, pte_t new_pte) { p4d_t *p4d = p4d_page + p4d_index(vaddr); pud_t *pud = fill_pud(p4d, vaddr); __set_pte_vaddr(pud, vaddr, new_pte); } void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte) { pud_t *pud = pud_page + pud_index(vaddr); __set_pte_vaddr(pud, vaddr, new_pte); } void set_pte_vaddr(unsigned long vaddr, pte_t pteval) { pgd_t *pgd; p4d_t *p4d_page; pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval)); pgd = pgd_offset_k(vaddr); if (pgd_none(*pgd)) { printk(KERN_ERR "PGD FIXMAP MISSING, it should be setup in head.S!\n"); return; } p4d_page = p4d_offset(pgd, 0); set_pte_vaddr_p4d(p4d_page, vaddr, pteval); } pmd_t * __init populate_extra_pmd(unsigned long vaddr) { pgd_t *pgd; p4d_t *p4d; pud_t *pud; pgd = pgd_offset_k(vaddr); p4d = fill_p4d(pgd, vaddr); pud = fill_pud(p4d, vaddr); return fill_pmd(pud, vaddr); } pte_t * __init populate_extra_pte(unsigned long vaddr) { pmd_t *pmd; pmd = populate_extra_pmd(vaddr); return fill_pte(pmd, vaddr); } /* * Create large page table mappings for a range of physical addresses. */ static void __init __init_extra_mapping(unsigned long phys, unsigned long size, enum page_cache_mode cache) { pgd_t *pgd; p4d_t *p4d; pud_t *pud; pmd_t *pmd; pgprot_t prot; pgprot_val(prot) = pgprot_val(PAGE_KERNEL_LARGE) | protval_4k_2_large(cachemode2protval(cache)); BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK)); for (; size; phys += PMD_SIZE, size -= PMD_SIZE) { pgd = pgd_offset_k((unsigned long)__va(phys)); if (pgd_none(*pgd)) { p4d = (p4d_t *) spp_getpage(); set_pgd(pgd, __pgd(__pa(p4d) | _KERNPG_TABLE | _PAGE_USER)); } p4d = p4d_offset(pgd, (unsigned long)__va(phys)); if (p4d_none(*p4d)) { pud = (pud_t *) spp_getpage(); set_p4d(p4d, __p4d(__pa(pud) | _KERNPG_TABLE | _PAGE_USER)); } pud = pud_offset(p4d, (unsigned long)__va(phys)); if (pud_none(*pud)) { pmd = (pmd_t *) spp_getpage(); set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE | _PAGE_USER)); } pmd = pmd_offset(pud, phys); BUG_ON(!pmd_none(*pmd)); set_pmd(pmd, __pmd(phys | pgprot_val(prot))); } } void __init init_extra_mapping_wb(unsigned long phys, unsigned long size) { __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_WB); } void __init init_extra_mapping_uc(unsigned long phys, unsigned long size) { __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_UC); } /* * The head.S code sets up the kernel high mapping: * * from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text) * * phys_base holds the negative offset to the kernel, which is added * to the compile time generated pmds. This results in invalid pmds up * to the point where we hit the physaddr 0 mapping. * * We limit the mappings to the region from _text to _brk_end. _brk_end * is rounded up to the 2MB boundary. This catches the invalid pmds as * well, as they are located before _text: */ void __init cleanup_highmap(void) { unsigned long vaddr = __START_KERNEL_map; unsigned long vaddr_end = __START_KERNEL_map + KERNEL_IMAGE_SIZE; unsigned long end = roundup((unsigned long)_brk_end, PMD_SIZE) - 1; pmd_t *pmd = level2_kernel_pgt; /* * Native path, max_pfn_mapped is not set yet. * Xen has valid max_pfn_mapped set in * arch/x86/xen/mmu.c:xen_setup_kernel_pagetable(). */ if (max_pfn_mapped) vaddr_end = __START_KERNEL_map + (max_pfn_mapped << PAGE_SHIFT); for (; vaddr + PMD_SIZE - 1 < vaddr_end; pmd++, vaddr += PMD_SIZE) { if (pmd_none(*pmd)) continue; if (vaddr < (unsigned long) _text || vaddr > end) set_pmd(pmd, __pmd(0)); } } /* * Create PTE level page table mapping for physical addresses. * It returns the last physical address mapped. */ static unsigned long __meminit phys_pte_init(pte_t *pte_page, unsigned long paddr, unsigned long paddr_end, pgprot_t prot, bool init) { unsigned long pages = 0, paddr_next; unsigned long paddr_last = paddr_end; pte_t *pte; int i; pte = pte_page + pte_index(paddr); i = pte_index(paddr); for (; i < PTRS_PER_PTE; i++, paddr = paddr_next, pte++) { paddr_next = (paddr & PAGE_MASK) + PAGE_SIZE; if (paddr >= paddr_end) { if (!after_bootmem && !e820__mapped_any(paddr & PAGE_MASK, paddr_next, E820_TYPE_RAM) && !e820__mapped_any(paddr & PAGE_MASK, paddr_next, E820_TYPE_RESERVED_KERN) && !e820__mapped_any(paddr & PAGE_MASK, paddr_next, E820_TYPE_ACPI)) set_pte_init(pte, __pte(0), init); continue; } /* * We will re-use the existing mapping. * Xen for example has some special requirements, like mapping * pagetable pages as RO. So assume someone who pre-setup * these mappings are more intelligent. */ if (!pte_none(*pte)) { if (!after_bootmem) pages++; continue; } if (0) pr_info(" pte=%p addr=%lx pte=%016lx\n", pte, paddr, pfn_pte(paddr >> PAGE_SHIFT, PAGE_KERNEL).pte); pages++; set_pte_init(pte, pfn_pte(paddr >> PAGE_SHIFT, prot), init); paddr_last = (paddr & PAGE_MASK) + PAGE_SIZE; } update_page_count(PG_LEVEL_4K, pages); return paddr_last; } /* * Create PMD level page table mapping for physical addresses. The virtual * and physical address have to be aligned at this level. * It returns the last physical address mapped. */ static unsigned long __meminit phys_pmd_init(pmd_t *pmd_page, unsigned long paddr, unsigned long paddr_end, unsigned long page_size_mask, pgprot_t prot, bool init) { unsigned long pages = 0, paddr_next; unsigned long paddr_last = paddr_end; int i = pmd_index(paddr); for (; i < PTRS_PER_PMD; i++, paddr = paddr_next) { pmd_t *pmd = pmd_page + pmd_index(paddr); pte_t *pte; pgprot_t new_prot = prot; paddr_next = (paddr & PMD_MASK) + PMD_SIZE; if (paddr >= paddr_end) { if (!after_bootmem && !e820__mapped_any(paddr & PMD_MASK, paddr_next, E820_TYPE_RAM) && !e820__mapped_any(paddr & PMD_MASK, paddr_next, E820_TYPE_RESERVED_KERN) && !e820__mapped_any(paddr & PMD_MASK, paddr_next, E820_TYPE_ACPI)) set_pmd_init(pmd, __pmd(0), init); continue; } if (!pmd_none(*pmd)) { if (!pmd_leaf(*pmd)) { spin_lock(&init_mm.page_table_lock); pte = (pte_t *)pmd_page_vaddr(*pmd); paddr_last = phys_pte_init(pte, paddr, paddr_end, prot, init); spin_unlock(&init_mm.page_table_lock); continue; } /* * If we are ok with PG_LEVEL_2M mapping, then we will * use the existing mapping, * * Otherwise, we will split the large page mapping but * use the same existing protection bits except for * large page, so that we don't violate Intel's TLB * Application note (317080) which says, while changing * the page sizes, new and old translations should * not differ with respect to page frame and * attributes. */ if (page_size_mask & (1 << PG_LEVEL_2M)) { if (!after_bootmem) pages++; paddr_last = paddr_next; continue; } new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd)); } if (page_size_mask & (1<> PAGE_SHIFT, prot_sethuge(prot)), init); spin_unlock(&init_mm.page_table_lock); paddr_last = paddr_next; continue; } pte = alloc_low_page(); paddr_last = phys_pte_init(pte, paddr, paddr_end, new_prot, init); spin_lock(&init_mm.page_table_lock); pmd_populate_kernel_init(&init_mm, pmd, pte, init); spin_unlock(&init_mm.page_table_lock); } update_page_count(PG_LEVEL_2M, pages); return paddr_last; } /* * Create PUD level page table mapping for physical addresses. The virtual * and physical address do not have to be aligned at this level. KASLR can * randomize virtual addresses up to this level. * It returns the last physical address mapped. */ static unsigned long __meminit phys_pud_init(pud_t *pud_page, unsigned long paddr, unsigned long paddr_end, unsigned long page_size_mask, pgprot_t _prot, bool init) { unsigned long pages = 0, paddr_next; unsigned long paddr_last = paddr_end; unsigned long vaddr = (unsigned long)__va(paddr); int i = pud_index(vaddr); for (; i < PTRS_PER_PUD; i++, paddr = paddr_next) { pud_t *pud; pmd_t *pmd; pgprot_t prot = _prot; vaddr = (unsigned long)__va(paddr); pud = pud_page + pud_index(vaddr); paddr_next = (paddr & PUD_MASK) + PUD_SIZE; if (paddr >= paddr_end) { if (!after_bootmem && !e820__mapped_any(paddr & PUD_MASK, paddr_next, E820_TYPE_RAM) && !e820__mapped_any(paddr & PUD_MASK, paddr_next, E820_TYPE_RESERVED_KERN) && !e820__mapped_any(paddr & PUD_MASK, paddr_next, E820_TYPE_ACPI)) set_pud_init(pud, __pud(0), init); continue; } if (!pud_none(*pud)) { if (!pud_leaf(*pud)) { pmd = pmd_offset(pud, 0); paddr_last = phys_pmd_init(pmd, paddr, paddr_end, page_size_mask, prot, init); continue; } /* * If we are ok with PG_LEVEL_1G mapping, then we will * use the existing mapping. * * Otherwise, we will split the gbpage mapping but use * the same existing protection bits except for large * page, so that we don't violate Intel's TLB * Application note (317080) which says, while changing * the page sizes, new and old translations should * not differ with respect to page frame and * attributes. */ if (page_size_mask & (1 << PG_LEVEL_1G)) { if (!after_bootmem) pages++; paddr_last = paddr_next; continue; } prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud)); } if (page_size_mask & (1<> PAGE_SHIFT, prot_sethuge(prot)), init); spin_unlock(&init_mm.page_table_lock); paddr_last = paddr_next; continue; } pmd = alloc_low_page(); paddr_last = phys_pmd_init(pmd, paddr, paddr_end, page_size_mask, prot, init); spin_lock(&init_mm.page_table_lock); pud_populate_init(&init_mm, pud, pmd, init); spin_unlock(&init_mm.page_table_lock); } update_page_count(PG_LEVEL_1G, pages); return paddr_last; } static unsigned long __meminit phys_p4d_init(p4d_t *p4d_page, unsigned long paddr, unsigned long paddr_end, unsigned long page_size_mask, pgprot_t prot, bool init) { unsigned long vaddr, vaddr_end, vaddr_next, paddr_next, paddr_last; paddr_last = paddr_end; vaddr = (unsigned long)__va(paddr); vaddr_end = (unsigned long)__va(paddr_end); if (!pgtable_l5_enabled()) return phys_pud_init((pud_t *) p4d_page, paddr, paddr_end, page_size_mask, prot, init); for (; vaddr < vaddr_end; vaddr = vaddr_next) { p4d_t *p4d = p4d_page + p4d_index(vaddr); pud_t *pud; vaddr_next = (vaddr & P4D_MASK) + P4D_SIZE; paddr = __pa(vaddr); if (paddr >= paddr_end) { paddr_next = __pa(vaddr_next); if (!after_bootmem && !e820__mapped_any(paddr & P4D_MASK, paddr_next, E820_TYPE_RAM) && !e820__mapped_any(paddr & P4D_MASK, paddr_next, E820_TYPE_RESERVED_KERN) && !e820__mapped_any(paddr & P4D_MASK, paddr_next, E820_TYPE_ACPI)) set_p4d_init(p4d, __p4d(0), init); continue; } if (!p4d_none(*p4d)) { pud = pud_offset(p4d, 0); paddr_last = phys_pud_init(pud, paddr, __pa(vaddr_end), page_size_mask, prot, init); continue; } pud = alloc_low_page(); paddr_last = phys_pud_init(pud, paddr, __pa(vaddr_end), page_size_mask, prot, init); spin_lock(&init_mm.page_table_lock); p4d_populate_init(&init_mm, p4d, pud, init); spin_unlock(&init_mm.page_table_lock); } return paddr_last; } static unsigned long __meminit __kernel_physical_mapping_init(unsigned long paddr_start, unsigned long paddr_end, unsigned long page_size_mask, pgprot_t prot, bool init) { bool pgd_changed = false; unsigned long vaddr, vaddr_start, vaddr_end, vaddr_next, paddr_last; paddr_last = paddr_end; vaddr = (unsigned long)__va(paddr_start); vaddr_end = (unsigned long)__va(paddr_end); vaddr_start = vaddr; for (; vaddr < vaddr_end; vaddr = vaddr_next) { pgd_t *pgd = pgd_offset_k(vaddr); p4d_t *p4d; vaddr_next = (vaddr & PGDIR_MASK) + PGDIR_SIZE; if (pgd_val(*pgd)) { p4d = (p4d_t *)pgd_page_vaddr(*pgd); paddr_last = phys_p4d_init(p4d, __pa(vaddr), __pa(vaddr_end), page_size_mask, prot, init); continue; } p4d = alloc_low_page(); paddr_last = phys_p4d_init(p4d, __pa(vaddr), __pa(vaddr_end), page_size_mask, prot, init); spin_lock(&init_mm.page_table_lock); if (pgtable_l5_enabled()) pgd_populate_init(&init_mm, pgd, p4d, init); else p4d_populate_init(&init_mm, p4d_offset(pgd, vaddr), (pud_t *) p4d, init); spin_unlock(&init_mm.page_table_lock); pgd_changed = true; } if (pgd_changed) sync_global_pgds(vaddr_start, vaddr_end - 1); return paddr_last; } /* * Create page table mapping for the physical memory for specific physical * addresses. Note that it can only be used to populate non-present entries. * The virtual and physical addresses have to be aligned on PMD level * down. It returns the last physical address mapped. */ unsigned long __meminit kernel_physical_mapping_init(unsigned long paddr_start, unsigned long paddr_end, unsigned long page_size_mask, pgprot_t prot) { return __kernel_physical_mapping_init(paddr_start, paddr_end, page_size_mask, prot, true); } /* * This function is similar to kernel_physical_mapping_init() above with the * exception that it uses set_{pud,pmd}() instead of the set_{pud,pte}_safe() * when updating the mapping. The caller is responsible to flush the TLBs after * the function returns. */ unsigned long __meminit kernel_physical_mapping_change(unsigned long paddr_start, unsigned long paddr_end, unsigned long page_size_mask) { return __kernel_physical_mapping_init(paddr_start, paddr_end, page_size_mask, PAGE_KERNEL, false); } #ifndef CONFIG_NUMA void __init initmem_init(void) { memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0); } #endif void __init paging_init(void) { sparse_init(); /* * clear the default setting with node 0 * note: don't use nodes_clear here, that is really clearing when * numa support is not compiled in, and later node_set_state * will not set it back. */ node_clear_state(0, N_MEMORY); node_clear_state(0, N_NORMAL_MEMORY); zone_sizes_init(); } #ifdef CONFIG_SPARSEMEM_VMEMMAP #define PAGE_UNUSED 0xFD /* * The unused vmemmap range, which was not yet memset(PAGE_UNUSED), ranges * from unused_pmd_start to next PMD_SIZE boundary. */ static unsigned long unused_pmd_start __meminitdata; static void __meminit vmemmap_flush_unused_pmd(void) { if (!unused_pmd_start) return; /* * Clears (unused_pmd_start, PMD_END] */ memset((void *)unused_pmd_start, PAGE_UNUSED, ALIGN(unused_pmd_start, PMD_SIZE) - unused_pmd_start); unused_pmd_start = 0; } #ifdef CONFIG_MEMORY_HOTPLUG /* Returns true if the PMD is completely unused and thus it can be freed */ static bool __meminit vmemmap_pmd_is_unused(unsigned long addr, unsigned long end) { unsigned long start = ALIGN_DOWN(addr, PMD_SIZE); /* * Flush the unused range cache to ensure that memchr_inv() will work * for the whole range. */ vmemmap_flush_unused_pmd(); memset((void *)addr, PAGE_UNUSED, end - addr); return !memchr_inv((void *)start, PAGE_UNUSED, PMD_SIZE); } #endif static void __meminit __vmemmap_use_sub_pmd(unsigned long start) { /* * As we expect to add in the same granularity as we remove, it's * sufficient to mark only some piece used to block the memmap page from * getting removed when removing some other adjacent memmap (just in * case the first memmap never gets initialized e.g., because the memory * block never gets onlined). */ memset((void *)start, 0, sizeof(struct page)); } static void __meminit vmemmap_use_sub_pmd(unsigned long start, unsigned long end) { /* * We only optimize if the new used range directly follows the * previously unused range (esp., when populating consecutive sections). */ if (unused_pmd_start == start) { if (likely(IS_ALIGNED(end, PMD_SIZE))) unused_pmd_start = 0; else unused_pmd_start = end; return; } /* * If the range does not contiguously follows previous one, make sure * to mark the unused range of the previous one so it can be removed. */ vmemmap_flush_unused_pmd(); __vmemmap_use_sub_pmd(start); } static void __meminit vmemmap_use_new_sub_pmd(unsigned long start, unsigned long end) { const unsigned long page = ALIGN_DOWN(start, PMD_SIZE); vmemmap_flush_unused_pmd(); /* * Could be our memmap page is filled with PAGE_UNUSED already from a * previous remove. Make sure to reset it. */ __vmemmap_use_sub_pmd(start); /* * Mark with PAGE_UNUSED the unused parts of the new memmap range */ if (!IS_ALIGNED(start, PMD_SIZE)) memset((void *)page, PAGE_UNUSED, start - page); /* * We want to avoid memset(PAGE_UNUSED) when populating the vmemmap of * consecutive sections. Remember for the last added PMD where the * unused range begins. */ if (!IS_ALIGNED(end, PMD_SIZE)) unused_pmd_start = end; } #endif /* * Memory hotplug specific functions */ #ifdef CONFIG_MEMORY_HOTPLUG /* * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need * updating. */ static void update_end_of_memory_vars(u64 start, u64 size) { unsigned long end_pfn = PFN_UP(start + size); if (end_pfn > max_pfn) { max_pfn = end_pfn; max_low_pfn = end_pfn; high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1; } } int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages, struct mhp_params *params) { int ret; ret = __add_pages(nid, start_pfn, nr_pages, params); WARN_ON_ONCE(ret); /* update max_pfn, max_low_pfn and high_memory */ update_end_of_memory_vars(start_pfn << PAGE_SHIFT, nr_pages << PAGE_SHIFT); return ret; } int arch_add_memory(int nid, u64 start, u64 size, struct mhp_params *params) { unsigned long start_pfn = start >> PAGE_SHIFT; unsigned long nr_pages = size >> PAGE_SHIFT; init_memory_mapping(start, start + size, params->pgprot); return add_pages(nid, start_pfn, nr_pages, params); } static void __meminit free_pagetable(struct page *page, int order) { unsigned long magic; unsigned int nr_pages = 1 << order; /* bootmem page has reserved flag */ if (PageReserved(page)) { __ClearPageReserved(page); magic = page->index; if (magic == SECTION_INFO || magic == MIX_SECTION_INFO) { while (nr_pages--) put_page_bootmem(page++); } else while (nr_pages--) free_reserved_page(page++); } else free_pages((unsigned long)page_address(page), order); } static void __meminit free_hugepage_table(struct page *page, struct vmem_altmap *altmap) { if (altmap) vmem_altmap_free(altmap, PMD_SIZE / PAGE_SIZE); else free_pagetable(page, get_order(PMD_SIZE)); } static void __meminit free_pte_table(pte_t *pte_start, pmd_t *pmd) { pte_t *pte; int i; for (i = 0; i < PTRS_PER_PTE; i++) { pte = pte_start + i; if (!pte_none(*pte)) return; } /* free a pte table */ free_pagetable(pmd_page(*pmd), 0); spin_lock(&init_mm.page_table_lock); pmd_clear(pmd); spin_unlock(&init_mm.page_table_lock); } static void __meminit free_pmd_table(pmd_t *pmd_start, pud_t *pud) { pmd_t *pmd; int i; for (i = 0; i < PTRS_PER_PMD; i++) { pmd = pmd_start + i; if (!pmd_none(*pmd)) return; } /* free a pmd table */ free_pagetable(pud_page(*pud), 0); spin_lock(&init_mm.page_table_lock); pud_clear(pud); spin_unlock(&init_mm.page_table_lock); } static void __meminit free_pud_table(pud_t *pud_start, p4d_t *p4d) { pud_t *pud; int i; for (i = 0; i < PTRS_PER_PUD; i++) { pud = pud_start + i; if (!pud_none(*pud)) return; } /* free a pud table */ free_pagetable(p4d_page(*p4d), 0); spin_lock(&init_mm.page_table_lock); p4d_clear(p4d); spin_unlock(&init_mm.page_table_lock); } static void __meminit remove_pte_table(pte_t *pte_start, unsigned long addr, unsigned long end, bool direct) { unsigned long next, pages = 0; pte_t *pte; phys_addr_t phys_addr; pte = pte_start + pte_index(addr); for (; addr < end; addr = next, pte++) { next = (addr + PAGE_SIZE) & PAGE_MASK; if (next > end) next = end; if (!pte_present(*pte)) continue; /* * We mapped [0,1G) memory as identity mapping when * initializing, in arch/x86/kernel/head_64.S. These * pagetables cannot be removed. */ phys_addr = pte_val(*pte) + (addr & PAGE_MASK); if (phys_addr < (phys_addr_t)0x40000000) return; if (!direct) free_pagetable(pte_page(*pte), 0); spin_lock(&init_mm.page_table_lock); pte_clear(&init_mm, addr, pte); spin_unlock(&init_mm.page_table_lock); /* For non-direct mapping, pages means nothing. */ pages++; } /* Call free_pte_table() in remove_pmd_table(). */ flush_tlb_all(); if (direct) update_page_count(PG_LEVEL_4K, -pages); } static void __meminit remove_pmd_table(pmd_t *pmd_start, unsigned long addr, unsigned long end, bool direct, struct vmem_altmap *altmap) { unsigned long next, pages = 0; pte_t *pte_base; pmd_t *pmd; pmd = pmd_start + pmd_index(addr); for (; addr < end; addr = next, pmd++) { next = pmd_addr_end(addr, end); if (!pmd_present(*pmd)) continue; if (pmd_leaf(*pmd)) { if (IS_ALIGNED(addr, PMD_SIZE) && IS_ALIGNED(next, PMD_SIZE)) { if (!direct) free_hugepage_table(pmd_page(*pmd), altmap); spin_lock(&init_mm.page_table_lock); pmd_clear(pmd); spin_unlock(&init_mm.page_table_lock); pages++; } #ifdef CONFIG_SPARSEMEM_VMEMMAP else if (vmemmap_pmd_is_unused(addr, next)) { free_hugepage_table(pmd_page(*pmd), altmap); spin_lock(&init_mm.page_table_lock); pmd_clear(pmd); spin_unlock(&init_mm.page_table_lock); } #endif continue; } pte_base = (pte_t *)pmd_page_vaddr(*pmd); remove_pte_table(pte_base, addr, next, direct); free_pte_table(pte_base, pmd); } /* Call free_pmd_table() in remove_pud_table(). */ if (direct) update_page_count(PG_LEVEL_2M, -pages); } static void __meminit remove_pud_table(pud_t *pud_start, unsigned long addr, unsigned long end, struct vmem_altmap *altmap, bool direct) { unsigned long next, pages = 0; pmd_t *pmd_base; pud_t *pud; pud = pud_start + pud_index(addr); for (; addr < end; addr = next, pud++) { next = pud_addr_end(addr, end); if (!pud_present(*pud)) continue; if (pud_leaf(*pud) && IS_ALIGNED(addr, PUD_SIZE) && IS_ALIGNED(next, PUD_SIZE)) { spin_lock(&init_mm.page_table_lock); pud_clear(pud); spin_unlock(&init_mm.page_table_lock); pages++; continue; } pmd_base = pmd_offset(pud, 0); remove_pmd_table(pmd_base, addr, next, direct, altmap); free_pmd_table(pmd_base, pud); } if (direct) update_page_count(PG_LEVEL_1G, -pages); } static void __meminit remove_p4d_table(p4d_t *p4d_start, unsigned long addr, unsigned long end, struct vmem_altmap *altmap, bool direct) { unsigned long next, pages = 0; pud_t *pud_base; p4d_t *p4d; p4d = p4d_start + p4d_index(addr); for (; addr < end; addr = next, p4d++) { next = p4d_addr_end(addr, end); if (!p4d_present(*p4d)) continue; BUILD_BUG_ON(p4d_leaf(*p4d)); pud_base = pud_offset(p4d, 0); remove_pud_table(pud_base, addr, next, altmap, direct); /* * For 4-level page tables we do not want to free PUDs, but in the * 5-level case we should free them. This code will have to change * to adapt for boot-time switching between 4 and 5 level page tables. */ if (pgtable_l5_enabled()) free_pud_table(pud_base, p4d); } if (direct) update_page_count(PG_LEVEL_512G, -pages); } /* start and end are both virtual address. */ static void __meminit remove_pagetable(unsigned long start, unsigned long end, bool direct, struct vmem_altmap *altmap) { unsigned long next; unsigned long addr; pgd_t *pgd; p4d_t *p4d; for (addr = start; addr < end; addr = next) { next = pgd_addr_end(addr, end); pgd = pgd_offset_k(addr); if (!pgd_present(*pgd)) continue; p4d = p4d_offset(pgd, 0); remove_p4d_table(p4d, addr, next, altmap, direct); } flush_tlb_all(); } void __ref vmemmap_free(unsigned long start, unsigned long end, struct vmem_altmap *altmap) { VM_BUG_ON(!PAGE_ALIGNED(start)); VM_BUG_ON(!PAGE_ALIGNED(end)); remove_pagetable(start, end, false, altmap); } static void __meminit kernel_physical_mapping_remove(unsigned long start, unsigned long end) { start = (unsigned long)__va(start); end = (unsigned long)__va(end); remove_pagetable(start, end, true, NULL); } void __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap) { unsigned long start_pfn = start >> PAGE_SHIFT; unsigned long nr_pages = size >> PAGE_SHIFT; __remove_pages(start_pfn, nr_pages, altmap); kernel_physical_mapping_remove(start, start + size); } #endif /* CONFIG_MEMORY_HOTPLUG */ static struct kcore_list kcore_vsyscall; static void __init register_page_bootmem_info(void) { #if defined(CONFIG_NUMA) || defined(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP) int i; for_each_online_node(i) register_page_bootmem_info_node(NODE_DATA(i)); #endif } /* * Pre-allocates page-table pages for the vmalloc area in the kernel page-table. * Only the level which needs to be synchronized between all page-tables is * allocated because the synchronization can be expensive. */ static void __init preallocate_vmalloc_pages(void) { unsigned long addr; const char *lvl; for (addr = VMALLOC_START; addr <= VMEMORY_END; addr = ALIGN(addr + 1, PGDIR_SIZE)) { pgd_t *pgd = pgd_offset_k(addr); p4d_t *p4d; pud_t *pud; lvl = "p4d"; p4d = p4d_alloc(&init_mm, pgd, addr); if (!p4d) goto failed; if (pgtable_l5_enabled()) continue; /* * The goal here is to allocate all possibly required * hardware page tables pointed to by the top hardware * level. * * On 4-level systems, the P4D layer is folded away and * the above code does no preallocation. Below, go down * to the pud _software_ level to ensure the second * hardware level is allocated on 4-level systems too. */ lvl = "pud"; pud = pud_alloc(&init_mm, p4d, addr); if (!pud) goto failed; } return; failed: /* * The pages have to be there now or they will be missing in * process page-tables later. */ panic("Failed to pre-allocate %s pages for vmalloc area\n", lvl); } void __init mem_init(void) { pci_iommu_alloc(); /* clear_bss() already clear the empty_zero_page */ /* this will put all memory onto the freelists */ memblock_free_all(); after_bootmem = 1; x86_init.hyper.init_after_bootmem(); /* * Must be done after boot memory is put on freelist, because here we * might set fields in deferred struct pages that have not yet been * initialized, and memblock_free_all() initializes all the reserved * deferred pages for us. */ register_page_bootmem_info(); /* Register memory areas for /proc/kcore */ if (get_gate_vma(&init_mm)) kclist_add(&kcore_vsyscall, (void *)VSYSCALL_ADDR, PAGE_SIZE, KCORE_USER); preallocate_vmalloc_pages(); } #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT int __init deferred_page_init_max_threads(const struct cpumask *node_cpumask) { /* * More CPUs always led to greater speedups on tested systems, up to * all the nodes' CPUs. Use all since the system is otherwise idle * now. */ return max_t(int, cpumask_weight(node_cpumask), 1); } #endif int kernel_set_to_readonly; void mark_rodata_ro(void) { unsigned long start = PFN_ALIGN(_text); unsigned long rodata_start = PFN_ALIGN(__start_rodata); unsigned long end = (unsigned long)__end_rodata_hpage_align; unsigned long text_end = PFN_ALIGN(_etext); unsigned long rodata_end = PFN_ALIGN(__end_rodata); unsigned long all_end; printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n", (end - start) >> 10); set_memory_ro(start, (end - start) >> PAGE_SHIFT); kernel_set_to_readonly = 1; /* * The rodata/data/bss/brk section (but not the kernel text!) * should also be not-executable. * * We align all_end to PMD_SIZE because the existing mapping * is a full PMD. If we would align _brk_end to PAGE_SIZE we * split the PMD and the reminder between _brk_end and the end * of the PMD will remain mapped executable. * * Any PMD which was setup after the one which covers _brk_end * has been zapped already via cleanup_highmem(). */ all_end = roundup((unsigned long)_brk_end, PMD_SIZE); set_memory_nx(text_end, (all_end - text_end) >> PAGE_SHIFT); set_ftrace_ops_ro(); #ifdef CONFIG_CPA_DEBUG printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end); set_memory_rw(start, (end-start) >> PAGE_SHIFT); printk(KERN_INFO "Testing CPA: again\n"); set_memory_ro(start, (end-start) >> PAGE_SHIFT); #endif free_kernel_image_pages("unused kernel image (text/rodata gap)", (void *)text_end, (void *)rodata_start); free_kernel_image_pages("unused kernel image (rodata/data gap)", (void *)rodata_end, (void *)_sdata); } /* * Block size is the minimum amount of memory which can be hotplugged or * hotremoved. It must be power of two and must be equal or larger than * MIN_MEMORY_BLOCK_SIZE. */ #define MAX_BLOCK_SIZE (2UL << 30) /* Amount of ram needed to start using large blocks */ #define MEM_SIZE_FOR_LARGE_BLOCK (64UL << 30) /* Adjustable memory block size */ static unsigned long set_memory_block_size; int __init set_memory_block_size_order(unsigned int order) { unsigned long size = 1UL << order; if (size > MEM_SIZE_FOR_LARGE_BLOCK || size < MIN_MEMORY_BLOCK_SIZE) return -EINVAL; set_memory_block_size = size; return 0; } static unsigned long probe_memory_block_size(void) { unsigned long boot_mem_end = max_pfn << PAGE_SHIFT; unsigned long bz; /* If memory block size has been set, then use it */ bz = set_memory_block_size; if (bz) goto done; /* Use regular block if RAM is smaller than MEM_SIZE_FOR_LARGE_BLOCK */ if (boot_mem_end < MEM_SIZE_FOR_LARGE_BLOCK) { bz = MIN_MEMORY_BLOCK_SIZE; goto done; } /* * Use max block size to minimize overhead on bare metal, where * alignment for memory hotplug isn't a concern. */ if (!boot_cpu_has(X86_FEATURE_HYPERVISOR)) { bz = MAX_BLOCK_SIZE; goto done; } /* Find the largest allowed block size that aligns to memory end */ for (bz = MAX_BLOCK_SIZE; bz > MIN_MEMORY_BLOCK_SIZE; bz >>= 1) { if (IS_ALIGNED(boot_mem_end, bz)) break; } done: pr_info("x86/mm: Memory block size: %ldMB\n", bz >> 20); return bz; } static unsigned long memory_block_size_probed; unsigned long memory_block_size_bytes(void) { if (!memory_block_size_probed) memory_block_size_probed = probe_memory_block_size(); return memory_block_size_probed; } #ifdef CONFIG_SPARSEMEM_VMEMMAP /* * Initialise the sparsemem vmemmap using huge-pages at the PMD level. */ static long __meminitdata addr_start, addr_end; static void __meminitdata *p_start, *p_end; static int __meminitdata node_start; void __meminit vmemmap_set_pmd(pmd_t *pmd, void *p, int node, unsigned long addr, unsigned long next) { pte_t entry; entry = pfn_pte(__pa(p) >> PAGE_SHIFT, PAGE_KERNEL_LARGE); set_pmd(pmd, __pmd(pte_val(entry))); /* check to see if we have contiguous blocks */ if (p_end != p || node_start != node) { if (p_start) pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n", addr_start, addr_end-1, p_start, p_end-1, node_start); addr_start = addr; node_start = node; p_start = p; } addr_end = addr + PMD_SIZE; p_end = p + PMD_SIZE; if (!IS_ALIGNED(addr, PMD_SIZE) || !IS_ALIGNED(next, PMD_SIZE)) vmemmap_use_new_sub_pmd(addr, next); } int __meminit vmemmap_check_pmd(pmd_t *pmd, int node, unsigned long addr, unsigned long next) { int large = pmd_leaf(*pmd); if (pmd_leaf(*pmd)) { vmemmap_verify((pte_t *)pmd, node, addr, next); vmemmap_use_sub_pmd(addr, next); } return large; } int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, struct vmem_altmap *altmap) { int err; VM_BUG_ON(!PAGE_ALIGNED(start)); VM_BUG_ON(!PAGE_ALIGNED(end)); if (end - start < PAGES_PER_SECTION * sizeof(struct page)) err = vmemmap_populate_basepages(start, end, node, NULL); else if (boot_cpu_has(X86_FEATURE_PSE)) err = vmemmap_populate_hugepages(start, end, node, altmap); else if (altmap) { pr_err_once("%s: no cpu support for altmap allocations\n", __func__); err = -ENOMEM; } else err = vmemmap_populate_basepages(start, end, node, NULL); if (!err) sync_global_pgds(start, end - 1); return err; } #ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE void register_page_bootmem_memmap(unsigned long section_nr, struct page *start_page, unsigned long nr_pages) { unsigned long addr = (unsigned long)start_page; unsigned long end = (unsigned long)(start_page + nr_pages); unsigned long next; pgd_t *pgd; p4d_t *p4d; pud_t *pud; pmd_t *pmd; unsigned int nr_pmd_pages; struct page *page; for (; addr < end; addr = next) { pte_t *pte = NULL; pgd = pgd_offset_k(addr); if (pgd_none(*pgd)) { next = (addr + PAGE_SIZE) & PAGE_MASK; continue; } get_page_bootmem(section_nr, pgd_page(*pgd), MIX_SECTION_INFO); p4d = p4d_offset(pgd, addr); if (p4d_none(*p4d)) { next = (addr + PAGE_SIZE) & PAGE_MASK; continue; } get_page_bootmem(section_nr, p4d_page(*p4d), MIX_SECTION_INFO); pud = pud_offset(p4d, addr); if (pud_none(*pud)) { next = (addr + PAGE_SIZE) & PAGE_MASK; continue; } get_page_bootmem(section_nr, pud_page(*pud), MIX_SECTION_INFO); if (!boot_cpu_has(X86_FEATURE_PSE)) { next = (addr + PAGE_SIZE) & PAGE_MASK; pmd = pmd_offset(pud, addr); if (pmd_none(*pmd)) continue; get_page_bootmem(section_nr, pmd_page(*pmd), MIX_SECTION_INFO); pte = pte_offset_kernel(pmd, addr); if (pte_none(*pte)) continue; get_page_bootmem(section_nr, pte_page(*pte), SECTION_INFO); } else { next = pmd_addr_end(addr, end); pmd = pmd_offset(pud, addr); if (pmd_none(*pmd)) continue; nr_pmd_pages = 1 << get_order(PMD_SIZE); page = pmd_page(*pmd); while (nr_pmd_pages--) get_page_bootmem(section_nr, page++, SECTION_INFO); } } } #endif void __meminit vmemmap_populate_print_last(void) { if (p_start) { pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n", addr_start, addr_end-1, p_start, p_end-1, node_start); p_start = NULL; p_end = NULL; node_start = 0; } } #endif