/* * 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 "mm_internal.h" static void ident_pmd_init(unsigned long pmd_flag, pmd_t *pmd_page, unsigned long addr, unsigned long end) { addr &= PMD_MASK; for (; addr < end; addr += PMD_SIZE) { pmd_t *pmd = pmd_page + pmd_index(addr); if (!pmd_present(*pmd)) set_pmd(pmd, __pmd(addr | pmd_flag)); } } static int ident_pud_init(struct x86_mapping_info *info, pud_t *pud_page, unsigned long addr, unsigned long end) { unsigned long next; for (; addr < end; addr = next) { pud_t *pud = pud_page + pud_index(addr); pmd_t *pmd; next = (addr & PUD_MASK) + PUD_SIZE; if (next > end) next = end; if (pud_present(*pud)) { pmd = pmd_offset(pud, 0); ident_pmd_init(info->pmd_flag, pmd, addr, next); continue; } pmd = (pmd_t *)info->alloc_pgt_page(info->context); if (!pmd) return -ENOMEM; ident_pmd_init(info->pmd_flag, pmd, addr, next); set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE)); } return 0; } int kernel_ident_mapping_init(struct x86_mapping_info *info, pgd_t *pgd_page, unsigned long addr, unsigned long end) { unsigned long next; int result; int off = info->kernel_mapping ? pgd_index(__PAGE_OFFSET) : 0; for (; addr < end; addr = next) { pgd_t *pgd = pgd_page + pgd_index(addr) + off; pud_t *pud; next = (addr & PGDIR_MASK) + PGDIR_SIZE; if (next > end) next = end; if (pgd_present(*pgd)) { pud = pud_offset(pgd, 0); result = ident_pud_init(info, pud, addr, next); if (result) return result; continue; } pud = (pud_t *)info->alloc_pgt_page(info->context); if (!pud) return -ENOMEM; result = ident_pud_init(info, pud, addr, next); if (result) return result; set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE)); } return 0; } static int __init parse_direct_gbpages_off(char *arg) { direct_gbpages = 0; return 0; } early_param("nogbpages", parse_direct_gbpages_off); static int __init parse_direct_gbpages_on(char *arg) { direct_gbpages = 1; return 0; } early_param("gbpages", parse_direct_gbpages_on); /* * 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. */ pteval_t __supported_pte_mask __read_mostly = ~_PAGE_IOMAP; EXPORT_SYMBOL_GPL(__supported_pte_mask); int force_personality32; /* * noexec32=on|off * Control non executable heap for 32bit processes. * To control the stack too use noexec=off * * on PROT_READ does not imply PROT_EXEC for 32-bit processes (default) * off PROT_READ implies PROT_EXEC */ static int __init nonx32_setup(char *str) { if (!strcmp(str, "on")) force_personality32 &= ~READ_IMPLIES_EXEC; else if (!strcmp(str, "off")) force_personality32 |= READ_IMPLIES_EXEC; return 1; } __setup("noexec32=", nonx32_setup); /* * When memory was added/removed make sure all the processes MM have * suitable PGD entries in the local PGD level page. */ void sync_global_pgds(unsigned long start, unsigned long end) { unsigned long address; for (address = start; address <= end; address += PGDIR_SIZE) { const pgd_t *pgd_ref = pgd_offset_k(address); struct page *page; 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(address); /* the pgt_lock only for Xen */ pgt_lock = &pgd_page_get_mm(page)->page_table_lock; spin_lock(pgt_lock); if (pgd_none(*pgd)) set_pgd(pgd, *pgd_ref); else BUG_ON(pgd_page_vaddr(*pgd) != pgd_page_vaddr(*pgd_ref)); spin_unlock(pgt_lock); } spin_unlock(&pgd_lock); } } /* * 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 | __GFP_NOTRACK); else ptr = alloc_bootmem_pages(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 pud_t *fill_pud(pgd_t *pgd, unsigned long vaddr) { if (pgd_none(*pgd)) { pud_t *pud = (pud_t *)spp_getpage(); pgd_populate(&init_mm, pgd, pud); if (pud != pud_offset(pgd, 0)) printk(KERN_ERR "PAGETABLE BUG #00! %p <-> %p\n", pud, pud_offset(pgd, 0)); } return pud_offset(pgd, 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 #01! %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 #02!\n"); } return pte_offset_kernel(pmd, vaddr); } void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte) { pud_t *pud; pmd_t *pmd; pte_t *pte; pud = pud_page + pud_index(vaddr); pmd = fill_pmd(pud, vaddr); 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(vaddr); } void set_pte_vaddr(unsigned long vaddr, pte_t pteval) { pgd_t *pgd; pud_t *pud_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; } pud_page = (pud_t*)pgd_page_vaddr(*pgd); set_pte_vaddr_pud(pud_page, vaddr, pteval); } pmd_t * __init populate_extra_pmd(unsigned long vaddr) { pgd_t *pgd; pud_t *pud; pgd = pgd_offset_k(vaddr); pud = fill_pud(pgd, 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, pgprot_t prot) { pgd_t *pgd; pud_t *pud; pmd_t *pmd; 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)) { pud = (pud_t *) spp_getpage(); set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE | _PAGE_USER)); } pud = pud_offset(pgd, (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_KERNEL_LARGE); } void __init init_extra_mapping_uc(unsigned long phys, unsigned long size) { __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE_NOCACHE); } /* * The head.S code sets up the kernel high mapping: * * from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text) * * phys_addr 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)); } } static unsigned long __meminit phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end, pgprot_t prot) { unsigned long pages = 0, next; unsigned long last_map_addr = end; int i; pte_t *pte = pte_page + pte_index(addr); for (i = pte_index(addr); i < PTRS_PER_PTE; i++, addr = next, pte++) { next = (addr & PAGE_MASK) + PAGE_SIZE; if (addr >= end) { if (!after_bootmem && !e820_any_mapped(addr & PAGE_MASK, next, E820_RAM) && !e820_any_mapped(addr & PAGE_MASK, next, E820_RESERVED_KERN)) set_pte(pte, __pte(0)); 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_val(*pte)) { if (!after_bootmem) pages++; continue; } if (0) printk(" pte=%p addr=%lx pte=%016lx\n", pte, addr, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL).pte); pages++; set_pte(pte, pfn_pte(addr >> PAGE_SHIFT, prot)); last_map_addr = (addr & PAGE_MASK) + PAGE_SIZE; } update_page_count(PG_LEVEL_4K, pages); return last_map_addr; } static unsigned long __meminit phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end, unsigned long page_size_mask, pgprot_t prot) { unsigned long pages = 0, next; unsigned long last_map_addr = end; int i = pmd_index(address); for (; i < PTRS_PER_PMD; i++, address = next) { pmd_t *pmd = pmd_page + pmd_index(address); pte_t *pte; pgprot_t new_prot = prot; next = (address & PMD_MASK) + PMD_SIZE; if (address >= end) { if (!after_bootmem && !e820_any_mapped(address & PMD_MASK, next, E820_RAM) && !e820_any_mapped(address & PMD_MASK, next, E820_RESERVED_KERN)) set_pmd(pmd, __pmd(0)); continue; } if (pmd_val(*pmd)) { if (!pmd_large(*pmd)) { spin_lock(&init_mm.page_table_lock); pte = (pte_t *)pmd_page_vaddr(*pmd); last_map_addr = phys_pte_init(pte, address, end, prot); 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++; last_map_addr = next; continue; } new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd)); } if (page_size_mask & (1<> PAGE_SHIFT, __pgprot(pgprot_val(prot) | _PAGE_PSE))); spin_unlock(&init_mm.page_table_lock); last_map_addr = next; continue; } pte = alloc_low_page(); last_map_addr = phys_pte_init(pte, address, end, new_prot); spin_lock(&init_mm.page_table_lock); pmd_populate_kernel(&init_mm, pmd, pte); spin_unlock(&init_mm.page_table_lock); } update_page_count(PG_LEVEL_2M, pages); return last_map_addr; } static unsigned long __meminit phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end, unsigned long page_size_mask) { unsigned long pages = 0, next; unsigned long last_map_addr = end; int i = pud_index(addr); for (; i < PTRS_PER_PUD; i++, addr = next) { pud_t *pud = pud_page + pud_index(addr); pmd_t *pmd; pgprot_t prot = PAGE_KERNEL; next = (addr & PUD_MASK) + PUD_SIZE; if (addr >= end) { if (!after_bootmem && !e820_any_mapped(addr & PUD_MASK, next, E820_RAM) && !e820_any_mapped(addr & PUD_MASK, next, E820_RESERVED_KERN)) set_pud(pud, __pud(0)); continue; } if (pud_val(*pud)) { if (!pud_large(*pud)) { pmd = pmd_offset(pud, 0); last_map_addr = phys_pmd_init(pmd, addr, end, page_size_mask, prot); __flush_tlb_all(); 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++; last_map_addr = next; continue; } prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud)); } if (page_size_mask & (1<> PAGE_SHIFT, PAGE_KERNEL_LARGE)); spin_unlock(&init_mm.page_table_lock); last_map_addr = next; continue; } pmd = alloc_low_page(); last_map_addr = phys_pmd_init(pmd, addr, end, page_size_mask, prot); spin_lock(&init_mm.page_table_lock); pud_populate(&init_mm, pud, pmd); spin_unlock(&init_mm.page_table_lock); } __flush_tlb_all(); update_page_count(PG_LEVEL_1G, pages); return last_map_addr; } unsigned long __meminit kernel_physical_mapping_init(unsigned long start, unsigned long end, unsigned long page_size_mask) { bool pgd_changed = false; unsigned long next, last_map_addr = end; unsigned long addr; start = (unsigned long)__va(start); end = (unsigned long)__va(end); addr = start; for (; start < end; start = next) { pgd_t *pgd = pgd_offset_k(start); pud_t *pud; next = (start & PGDIR_MASK) + PGDIR_SIZE; if (pgd_val(*pgd)) { pud = (pud_t *)pgd_page_vaddr(*pgd); last_map_addr = phys_pud_init(pud, __pa(start), __pa(end), page_size_mask); continue; } pud = alloc_low_page(); last_map_addr = phys_pud_init(pud, __pa(start), __pa(end), page_size_mask); spin_lock(&init_mm.page_table_lock); pgd_populate(&init_mm, pgd, pud); spin_unlock(&init_mm.page_table_lock); pgd_changed = true; } if (pgd_changed) sync_global_pgds(addr, end - 1); __flush_tlb_all(); return last_map_addr; } #ifndef CONFIG_NUMA void __init initmem_init(void) { memblock_set_node(0, (phys_addr_t)ULLONG_MAX, 0); } #endif void __init paging_init(void) { sparse_memory_present_with_active_regions(MAX_NUMNODES); 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); if (N_MEMORY != N_NORMAL_MEMORY) node_clear_state(0, N_NORMAL_MEMORY); zone_sizes_init(); } /* * 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; } } /* * Memory is added always to NORMAL zone. This means you will never get * additional DMA/DMA32 memory. */ int arch_add_memory(int nid, u64 start, u64 size) { struct pglist_data *pgdat = NODE_DATA(nid); struct zone *zone = pgdat->node_zones + ZONE_NORMAL; unsigned long start_pfn = start >> PAGE_SHIFT; unsigned long nr_pages = size >> PAGE_SHIFT; int ret; init_memory_mapping(start, start + size); ret = __add_pages(nid, zone, start_pfn, nr_pages); WARN_ON_ONCE(ret); /* update max_pfn, max_low_pfn and high_memory */ update_end_of_memory_vars(start, size); return ret; } EXPORT_SYMBOL_GPL(arch_add_memory); #define PAGE_INUSE 0xFD static void __meminit free_pagetable(struct page *page, int order) { struct zone *zone; bool bootmem = false; unsigned long magic; unsigned int nr_pages = 1 << order; /* bootmem page has reserved flag */ if (PageReserved(page)) { __ClearPageReserved(page); bootmem = true; magic = (unsigned long)page->lru.next; if (magic == SECTION_INFO || magic == MIX_SECTION_INFO) { while (nr_pages--) put_page_bootmem(page++); } else __free_pages_bootmem(page, order); } else free_pages((unsigned long)page_address(page), order); /* * SECTION_INFO pages and MIX_SECTION_INFO pages * are all allocated by bootmem. */ if (bootmem) { zone = page_zone(page); zone_span_writelock(zone); zone->present_pages += nr_pages; zone_span_writeunlock(zone); totalram_pages += nr_pages; } } 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_val(*pte)) return; } /* free a pte talbe */ free_pagetable(pmd_page(*pmd), 0); spin_lock(&init_mm.page_table_lock); pmd_clear(pmd); spin_unlock(&init_mm.page_table_lock); } static void __meminit free_pmd_table(pmd_t *pmd_start, pud_t *pud) { pmd_t *pmd; int i; for (i = 0; i < PTRS_PER_PMD; i++) { pmd = pmd_start + i; if (pmd_val(*pmd)) return; } /* free a pmd talbe */ free_pagetable(pud_page(*pud), 0); spin_lock(&init_mm.page_table_lock); pud_clear(pud); spin_unlock(&init_mm.page_table_lock); } /* Return true if pgd is changed, otherwise return false. */ static bool __meminit free_pud_table(pud_t *pud_start, pgd_t *pgd) { pud_t *pud; int i; for (i = 0; i < PTRS_PER_PUD; i++) { pud = pud_start + i; if (pud_val(*pud)) return false; } /* free a pud table */ free_pagetable(pgd_page(*pgd), 0); spin_lock(&init_mm.page_table_lock); pgd_clear(pgd); spin_unlock(&init_mm.page_table_lock); return true; } 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; void *page_addr; 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 (IS_ALIGNED(addr, PAGE_SIZE) && IS_ALIGNED(next, PAGE_SIZE)) { /* * Do not free direct mapping pages since they were * freed when offlining, or simplely not in use. */ 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++; } else { /* * If we are here, we are freeing vmemmap pages since * direct mapped memory ranges to be freed are aligned. * * If we are not removing the whole page, it means * other page structs in this page are being used and * we canot remove them. So fill the unused page_structs * with 0xFD, and remove the page when it is wholly * filled with 0xFD. */ memset((void *)addr, PAGE_INUSE, next - addr); page_addr = page_address(pte_page(*pte)); if (!memchr_inv(page_addr, PAGE_INUSE, PAGE_SIZE)) { 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); } } } /* 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) { unsigned long next, pages = 0; pte_t *pte_base; pmd_t *pmd; void *page_addr; pmd = pmd_start + pmd_index(addr); for (; addr < end; addr = next, pmd++) { next = pmd_addr_end(addr, end); if (!pmd_present(*pmd)) continue; if (pmd_large(*pmd)) { if (IS_ALIGNED(addr, PMD_SIZE) && IS_ALIGNED(next, PMD_SIZE)) { if (!direct) free_pagetable(pmd_page(*pmd), get_order(PMD_SIZE)); spin_lock(&init_mm.page_table_lock); pmd_clear(pmd); spin_unlock(&init_mm.page_table_lock); pages++; } else { /* If here, we are freeing vmemmap pages. */ memset((void *)addr, PAGE_INUSE, next - addr); page_addr = page_address(pmd_page(*pmd)); if (!memchr_inv(page_addr, PAGE_INUSE, PMD_SIZE)) { free_pagetable(pmd_page(*pmd), get_order(PMD_SIZE)); spin_lock(&init_mm.page_table_lock); pmd_clear(pmd); spin_unlock(&init_mm.page_table_lock); } } 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, bool direct) { unsigned long next, pages = 0; pmd_t *pmd_base; pud_t *pud; void *page_addr; pud = pud_start + pud_index(addr); for (; addr < end; addr = next, pud++) { next = pud_addr_end(addr, end); if (!pud_present(*pud)) continue; if (pud_large(*pud)) { if (IS_ALIGNED(addr, PUD_SIZE) && IS_ALIGNED(next, PUD_SIZE)) { if (!direct) free_pagetable(pud_page(*pud), get_order(PUD_SIZE)); spin_lock(&init_mm.page_table_lock); pud_clear(pud); spin_unlock(&init_mm.page_table_lock); pages++; } else { /* If here, we are freeing vmemmap pages. */ memset((void *)addr, PAGE_INUSE, next - addr); page_addr = page_address(pud_page(*pud)); if (!memchr_inv(page_addr, PAGE_INUSE, PUD_SIZE)) { free_pagetable(pud_page(*pud), get_order(PUD_SIZE)); spin_lock(&init_mm.page_table_lock); pud_clear(pud); spin_unlock(&init_mm.page_table_lock); } } continue; } pmd_base = (pmd_t *)pud_page_vaddr(*pud); remove_pmd_table(pmd_base, addr, next, direct); free_pmd_table(pmd_base, pud); } if (direct) update_page_count(PG_LEVEL_1G, -pages); } /* start and end are both virtual address. */ static void __meminit remove_pagetable(unsigned long start, unsigned long end, bool direct) { unsigned long next; pgd_t *pgd; pud_t *pud; bool pgd_changed = false; for (; start < end; start = next) { next = pgd_addr_end(start, end); pgd = pgd_offset_k(start); if (!pgd_present(*pgd)) continue; pud = (pud_t *)pgd_page_vaddr(*pgd); remove_pud_table(pud, start, next, direct); if (free_pud_table(pud, pgd)) pgd_changed = true; } if (pgd_changed) sync_global_pgds(start, end - 1); flush_tlb_all(); } void __ref vmemmap_free(struct page *memmap, unsigned long nr_pages) { unsigned long start = (unsigned long)memmap; unsigned long end = (unsigned long)(memmap + nr_pages); remove_pagetable(start, end, false); } #ifdef CONFIG_MEMORY_HOTREMOVE 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); } int __ref arch_remove_memory(u64 start, u64 size) { unsigned long start_pfn = start >> PAGE_SHIFT; unsigned long nr_pages = size >> PAGE_SHIFT; struct zone *zone; int ret; zone = page_zone(pfn_to_page(start_pfn)); kernel_physical_mapping_remove(start, start + size); ret = __remove_pages(zone, start_pfn, nr_pages); WARN_ON_ONCE(ret); return ret; } #endif #endif /* CONFIG_MEMORY_HOTPLUG */ static struct kcore_list kcore_vsyscall; static void __init register_page_bootmem_info(void) { #ifdef CONFIG_NUMA int i; for_each_online_node(i) register_page_bootmem_info_node(NODE_DATA(i)); #endif } void __init mem_init(void) { long codesize, reservedpages, datasize, initsize; unsigned long absent_pages; pci_iommu_alloc(); /* clear_bss() already clear the empty_zero_page */ reservedpages = 0; /* this will put all low memory onto the freelists */ register_page_bootmem_info(); totalram_pages = free_all_bootmem(); absent_pages = absent_pages_in_range(0, max_pfn); reservedpages = max_pfn - totalram_pages - absent_pages; after_bootmem = 1; codesize = (unsigned long) &_etext - (unsigned long) &_text; datasize = (unsigned long) &_edata - (unsigned long) &_etext; initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin; /* Register memory areas for /proc/kcore */ kclist_add(&kcore_vsyscall, (void *)VSYSCALL_START, VSYSCALL_END - VSYSCALL_START, KCORE_OTHER); printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, " "%ldk absent, %ldk reserved, %ldk data, %ldk init)\n", nr_free_pages() << (PAGE_SHIFT-10), max_pfn << (PAGE_SHIFT-10), codesize >> 10, absent_pages << (PAGE_SHIFT-10), reservedpages << (PAGE_SHIFT-10), datasize >> 10, initsize >> 10); } #ifdef CONFIG_DEBUG_RODATA const int rodata_test_data = 0xC3; EXPORT_SYMBOL_GPL(rodata_test_data); int kernel_set_to_readonly; void set_kernel_text_rw(void) { unsigned long start = PFN_ALIGN(_text); unsigned long end = PFN_ALIGN(__stop___ex_table); if (!kernel_set_to_readonly) return; pr_debug("Set kernel text: %lx - %lx for read write\n", start, end); /* * Make the kernel identity mapping for text RW. Kernel text * mapping will always be RO. Refer to the comment in * static_protections() in pageattr.c */ set_memory_rw(start, (end - start) >> PAGE_SHIFT); } void set_kernel_text_ro(void) { unsigned long start = PFN_ALIGN(_text); unsigned long end = PFN_ALIGN(__stop___ex_table); if (!kernel_set_to_readonly) return; pr_debug("Set kernel text: %lx - %lx for read only\n", start, end); /* * Set the kernel identity mapping for text RO. */ set_memory_ro(start, (end - start) >> PAGE_SHIFT); } 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(&__stop___ex_table); unsigned long rodata_end = PFN_ALIGN(&__end_rodata); unsigned long all_end = PFN_ALIGN(&_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. */ set_memory_nx(rodata_start, (all_end - rodata_start) >> PAGE_SHIFT); rodata_test(); #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_init_pages("unused kernel memory", (unsigned long) __va(__pa_symbol(text_end)), (unsigned long) __va(__pa_symbol(rodata_start))); free_init_pages("unused kernel memory", (unsigned long) __va(__pa_symbol(rodata_end)), (unsigned long) __va(__pa_symbol(_sdata))); } #endif int kern_addr_valid(unsigned long addr) { unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT; pgd_t *pgd; pud_t *pud; pmd_t *pmd; pte_t *pte; if (above != 0 && above != -1UL) return 0; pgd = pgd_offset_k(addr); if (pgd_none(*pgd)) return 0; pud = pud_offset(pgd, addr); if (pud_none(*pud)) return 0; if (pud_large(*pud)) return pfn_valid(pud_pfn(*pud)); pmd = pmd_offset(pud, addr); if (pmd_none(*pmd)) return 0; if (pmd_large(*pmd)) return pfn_valid(pmd_pfn(*pmd)); pte = pte_offset_kernel(pmd, addr); if (pte_none(*pte)) return 0; return pfn_valid(pte_pfn(*pte)); } /* * A pseudo VMA to allow ptrace access for the vsyscall page. This only * covers the 64bit vsyscall page now. 32bit has a real VMA now and does * not need special handling anymore: */ static struct vm_area_struct gate_vma = { .vm_start = VSYSCALL_START, .vm_end = VSYSCALL_START + (VSYSCALL_MAPPED_PAGES * PAGE_SIZE), .vm_page_prot = PAGE_READONLY_EXEC, .vm_flags = VM_READ | VM_EXEC }; struct vm_area_struct *get_gate_vma(struct mm_struct *mm) { #ifdef CONFIG_IA32_EMULATION if (!mm || mm->context.ia32_compat) return NULL; #endif return &gate_vma; } int in_gate_area(struct mm_struct *mm, unsigned long addr) { struct vm_area_struct *vma = get_gate_vma(mm); if (!vma) return 0; return (addr >= vma->vm_start) && (addr < vma->vm_end); } /* * Use this when you have no reliable mm, typically from interrupt * context. It is less reliable than using a task's mm and may give * false positives. */ int in_gate_area_no_mm(unsigned long addr) { return (addr >= VSYSCALL_START) && (addr < VSYSCALL_END); } const char *arch_vma_name(struct vm_area_struct *vma) { if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso) return "[vdso]"; if (vma == &gate_vma) return "[vsyscall]"; return NULL; } #ifdef CONFIG_X86_UV unsigned long memory_block_size_bytes(void) { if (is_uv_system()) { printk(KERN_INFO "UV: memory block size 2GB\n"); return 2UL * 1024 * 1024 * 1024; } return MIN_MEMORY_BLOCK_SIZE; } #endif #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; int __meminit vmemmap_populate(struct page *start_page, unsigned long size, int node) { unsigned long addr = (unsigned long)start_page; unsigned long end = (unsigned long)(start_page + size); unsigned long next; pgd_t *pgd; pud_t *pud; pmd_t *pmd; for (; addr < end; addr = next) { void *p = NULL; pgd = vmemmap_pgd_populate(addr, node); if (!pgd) return -ENOMEM; pud = vmemmap_pud_populate(pgd, addr, node); if (!pud) return -ENOMEM; if (!cpu_has_pse) { next = (addr + PAGE_SIZE) & PAGE_MASK; pmd = vmemmap_pmd_populate(pud, addr, node); if (!pmd) return -ENOMEM; p = vmemmap_pte_populate(pmd, addr, node); if (!p) return -ENOMEM; addr_end = addr + PAGE_SIZE; p_end = p + PAGE_SIZE; } else { next = pmd_addr_end(addr, end); pmd = pmd_offset(pud, addr); if (pmd_none(*pmd)) { pte_t entry; p = vmemmap_alloc_block_buf(PMD_SIZE, node); if (!p) return -ENOMEM; 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) printk(KERN_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; } else vmemmap_verify((pte_t *)pmd, node, addr, next); } } sync_global_pgds((unsigned long)start_page, end - 1); return 0; } #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HAVE_BOOTMEM_INFO_NODE) void register_page_bootmem_memmap(unsigned long section_nr, struct page *start_page, unsigned long size) { unsigned long addr = (unsigned long)start_page; unsigned long end = (unsigned long)(start_page + size); unsigned long next; pgd_t *pgd; pud_t *pud; pmd_t *pmd; unsigned int nr_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); pud = pud_offset(pgd, addr); if (pud_none(*pud)) { next = (addr + PAGE_SIZE) & PAGE_MASK; continue; } get_page_bootmem(section_nr, pud_page(*pud), MIX_SECTION_INFO); if (!cpu_has_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_pages = 1 << (get_order(PMD_SIZE)); page = pmd_page(*pmd); while (nr_pages--) get_page_bootmem(section_nr, page++, SECTION_INFO); } } } #endif void __meminit vmemmap_populate_print_last(void) { if (p_start) { printk(KERN_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