diff options
Diffstat (limited to 'kernel/arch/x86/mm/init_64.c')
| -rw-r--r-- | kernel/arch/x86/mm/init_64.c | 1376 |
1 files changed, 1376 insertions, 0 deletions
diff --git a/kernel/arch/x86/mm/init_64.c b/kernel/arch/x86/mm/init_64.c new file mode 100644 index 000000000..3fba623e3 --- /dev/null +++ b/kernel/arch/x86/mm/init_64.c @@ -0,0 +1,1376 @@ +/* + * linux/arch/x86_64/mm/init.c + * + * Copyright (C) 1995 Linus Torvalds + * Copyright (C) 2000 Pavel Machek <pavel@ucw.cz> + * Copyright (C) 2002,2003 Andi Kleen <ak@suse.de> + */ + +#include <linux/signal.h> +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/string.h> +#include <linux/types.h> +#include <linux/ptrace.h> +#include <linux/mman.h> +#include <linux/mm.h> +#include <linux/swap.h> +#include <linux/smp.h> +#include <linux/init.h> +#include <linux/initrd.h> +#include <linux/pagemap.h> +#include <linux/bootmem.h> +#include <linux/memblock.h> +#include <linux/proc_fs.h> +#include <linux/pci.h> +#include <linux/pfn.h> +#include <linux/poison.h> +#include <linux/dma-mapping.h> +#include <linux/module.h> +#include <linux/memory.h> +#include <linux/memory_hotplug.h> +#include <linux/nmi.h> +#include <linux/gfp.h> +#include <linux/kcore.h> + +#include <asm/processor.h> +#include <asm/bios_ebda.h> +#include <asm/uaccess.h> +#include <asm/pgtable.h> +#include <asm/pgalloc.h> +#include <asm/dma.h> +#include <asm/fixmap.h> +#include <asm/e820.h> +#include <asm/apic.h> +#include <asm/tlb.h> +#include <asm/mmu_context.h> +#include <asm/proto.h> +#include <asm/smp.h> +#include <asm/sections.h> +#include <asm/kdebug.h> +#include <asm/numa.h> +#include <asm/cacheflush.h> +#include <asm/init.h> +#include <asm/setup.h> + +#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; +} + +/* + * 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 = ~0; +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, int removed) +{ + unsigned long address; + + for (address = start; address <= end; address += PGDIR_SIZE) { + const pgd_t *pgd_ref = pgd_offset_k(address); + struct page *page; + + /* + * When it is called after memory hot remove, pgd_none() + * returns true. In this case (removed == 1), we must clear + * the PGD entries in the local PGD level page. + */ + if (pgd_none(*pgd_ref) && !removed) + 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_ref) && !pgd_none(*pgd)) + BUG_ON(pgd_page_vaddr(*pgd) + != pgd_page_vaddr(*pgd_ref)); + + if (removed) { + if (pgd_none(*pgd_ref) && !pgd_none(*pgd)) + pgd_clear(pgd); + } else { + if (pgd_none(*pgd)) + set_pgd(pgd, *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, + enum page_cache_mode cache) +{ + pgd_t *pgd; + pud_t *pud; + pmd_t *pmd; + pgprot_t prot; + + pgprot_val(prot) = pgprot_val(PAGE_KERNEL_LARGE) | + pgprot_val(pgprot_4k_2_large(cachemode2pgprot(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)) { + 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_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)); + } +} + +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<<PG_LEVEL_2M)) { + pages++; + spin_lock(&init_mm.page_table_lock); + set_pte((pte_t *)pmd, + pfn_pte((address & PMD_MASK) >> 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<<PG_LEVEL_1G)) { + pages++; + spin_lock(&init_mm.page_table_lock); + set_pte((pte_t *)pud, + pfn_pte((addr & PUD_MASK) >> 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, 0); + + __flush_tlb_all(); + + return last_map_addr; +} + +#ifndef CONFIG_NUMA +void __init initmem_init(void) +{ + memblock_set_node(0, (phys_addr_t)ULLONG_MAX, &memblock.memory, 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_for_memory(nid, start, size, 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) +{ + unsigned long magic; + unsigned int nr_pages = 1 << order; + + /* bootmem page has reserved flag */ + if (PageReserved(page)) { + __ClearPageReserved(page); + + magic = (unsigned long)page->lru.next; + 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_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; + unsigned long addr; + pgd_t *pgd; + pud_t *pud; + bool pgd_changed = false; + + for (addr = start; addr < end; addr = next) { + next = pgd_addr_end(addr, end); + + pgd = pgd_offset_k(addr); + if (!pgd_present(*pgd)) + continue; + + pud = (pud_t *)pgd_page_vaddr(*pgd); + remove_pud_table(pud, addr, next, direct); + if (free_pud_table(pud, pgd)) + pgd_changed = true; + } + + if (pgd_changed) + sync_global_pgds(start, end - 1, 1); + + flush_tlb_all(); +} + +void __ref vmemmap_free(unsigned long start, unsigned long end) +{ + 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) +{ + pci_iommu_alloc(); + + /* clear_bss() already clear the empty_zero_page */ + + register_page_bootmem_info(); + + /* this will put all memory onto the freelists */ + free_all_bootmem(); + after_bootmem = 1; + + /* Register memory areas for /proc/kcore */ + kclist_add(&kcore_vsyscall, (void *)VSYSCALL_ADDR, + PAGE_SIZE, KCORE_OTHER); + + mem_init_print_info(NULL); +} + +#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; + + 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(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", + (unsigned long) __va(__pa_symbol(text_end)), + (unsigned long) __va(__pa_symbol(rodata_start))); + free_init_pages("unused kernel", + (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)); +} + +static unsigned long probe_memory_block_size(void) +{ + /* start from 2g */ + unsigned long bz = 1UL<<31; + + if (totalram_pages >= (64ULL << (30 - PAGE_SHIFT))) { + pr_info("Using 2GB memory block size for large-memory system\n"); + return 2UL * 1024 * 1024 * 1024; + } + + /* less than 64g installed */ + if ((max_pfn << PAGE_SHIFT) < (16UL << 32)) + return MIN_MEMORY_BLOCK_SIZE; + + /* get the tail size */ + while (bz > MIN_MEMORY_BLOCK_SIZE) { + if (!((max_pfn << PAGE_SHIFT) & (bz - 1))) + break; + bz >>= 1; + } + + printk(KERN_DEBUG "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; + +static int __meminit vmemmap_populate_hugepages(unsigned long start, + unsigned long end, int node) +{ + unsigned long addr; + unsigned long next; + pgd_t *pgd; + pud_t *pud; + pmd_t *pmd; + + for (addr = start; addr < end; addr = next) { + next = pmd_addr_end(addr, end); + + pgd = vmemmap_pgd_populate(addr, node); + if (!pgd) + return -ENOMEM; + + pud = vmemmap_pud_populate(pgd, addr, node); + if (!pud) + return -ENOMEM; + + pmd = pmd_offset(pud, addr); + if (pmd_none(*pmd)) { + void *p; + + p = vmemmap_alloc_block_buf(PMD_SIZE, node); + if (p) { + 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) + 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; + continue; + } + } else if (pmd_large(*pmd)) { + vmemmap_verify((pte_t *)pmd, node, addr, next); + continue; + } + pr_warn_once("vmemmap: falling back to regular page backing\n"); + if (vmemmap_populate_basepages(addr, next, node)) + return -ENOMEM; + } + return 0; +} + +int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node) +{ + int err; + + if (cpu_has_pse) + err = vmemmap_populate_hugepages(start, end, node); + else + err = vmemmap_populate_basepages(start, end, node); + if (!err) + sync_global_pgds(start, end - 1, 0); + return err; +} + +#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 |