| #include <linux/ioport.h> |
| #include <linux/swap.h> |
| |
| #include <asm/cacheflush.h> |
| #include <asm/e820.h> |
| #include <asm/init.h> |
| #include <asm/page.h> |
| #include <asm/page_types.h> |
| #include <asm/sections.h> |
| #include <asm/system.h> |
| #include <asm/tlbflush.h> |
| |
| unsigned long __initdata e820_table_start; |
| unsigned long __meminitdata e820_table_end; |
| unsigned long __meminitdata e820_table_top; |
| |
| int after_bootmem; |
| |
| int direct_gbpages |
| #ifdef CONFIG_DIRECT_GBPAGES |
| = 1 |
| #endif |
| ; |
| |
| static void __init find_early_table_space(unsigned long end, int use_pse, |
| int use_gbpages) |
| { |
| unsigned long puds, pmds, ptes, tables, start; |
| |
| puds = (end + PUD_SIZE - 1) >> PUD_SHIFT; |
| tables = roundup(puds * sizeof(pud_t), PAGE_SIZE); |
| |
| if (use_gbpages) { |
| unsigned long extra; |
| |
| extra = end - ((end>>PUD_SHIFT) << PUD_SHIFT); |
| pmds = (extra + PMD_SIZE - 1) >> PMD_SHIFT; |
| } else |
| pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT; |
| |
| tables += roundup(pmds * sizeof(pmd_t), PAGE_SIZE); |
| |
| if (use_pse) { |
| unsigned long extra; |
| |
| extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT); |
| #ifdef CONFIG_X86_32 |
| extra += PMD_SIZE; |
| #endif |
| ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT; |
| } else |
| ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT; |
| |
| tables += roundup(ptes * sizeof(pte_t), PAGE_SIZE); |
| |
| #ifdef CONFIG_X86_32 |
| /* for fixmap */ |
| tables += roundup(__end_of_fixed_addresses * sizeof(pte_t), PAGE_SIZE); |
| #endif |
| |
| /* |
| * RED-PEN putting page tables only on node 0 could |
| * cause a hotspot and fill up ZONE_DMA. The page tables |
| * need roughly 0.5KB per GB. |
| */ |
| #ifdef CONFIG_X86_32 |
| start = 0x7000; |
| e820_table_start = find_e820_area(start, max_pfn_mapped<<PAGE_SHIFT, |
| tables, PAGE_SIZE); |
| #else /* CONFIG_X86_64 */ |
| start = 0x8000; |
| e820_table_start = find_e820_area(start, end, tables, PAGE_SIZE); |
| #endif |
| if (e820_table_start == -1UL) |
| panic("Cannot find space for the kernel page tables"); |
| |
| e820_table_start >>= PAGE_SHIFT; |
| e820_table_end = e820_table_start; |
| e820_table_top = e820_table_start + (tables >> PAGE_SHIFT); |
| |
| printk(KERN_DEBUG "kernel direct mapping tables up to %lx @ %lx-%lx\n", |
| end, e820_table_start << PAGE_SHIFT, e820_table_top << PAGE_SHIFT); |
| } |
| |
| struct map_range { |
| unsigned long start; |
| unsigned long end; |
| unsigned page_size_mask; |
| }; |
| |
| #ifdef CONFIG_X86_32 |
| #define NR_RANGE_MR 3 |
| #else /* CONFIG_X86_64 */ |
| #define NR_RANGE_MR 5 |
| #endif |
| |
| static int __meminit save_mr(struct map_range *mr, int nr_range, |
| unsigned long start_pfn, unsigned long end_pfn, |
| unsigned long page_size_mask) |
| { |
| if (start_pfn < end_pfn) { |
| if (nr_range >= NR_RANGE_MR) |
| panic("run out of range for init_memory_mapping\n"); |
| mr[nr_range].start = start_pfn<<PAGE_SHIFT; |
| mr[nr_range].end = end_pfn<<PAGE_SHIFT; |
| mr[nr_range].page_size_mask = page_size_mask; |
| nr_range++; |
| } |
| |
| return nr_range; |
| } |
| |
| #ifdef CONFIG_X86_64 |
| static void __init init_gbpages(void) |
| { |
| if (direct_gbpages && cpu_has_gbpages) |
| printk(KERN_INFO "Using GB pages for direct mapping\n"); |
| else |
| direct_gbpages = 0; |
| } |
| #else |
| static inline void init_gbpages(void) |
| { |
| } |
| #endif |
| |
| /* |
| * Setup the direct mapping of the physical memory at PAGE_OFFSET. |
| * This runs before bootmem is initialized and gets pages directly from |
| * the physical memory. To access them they are temporarily mapped. |
| */ |
| unsigned long __init_refok init_memory_mapping(unsigned long start, |
| unsigned long end) |
| { |
| unsigned long page_size_mask = 0; |
| unsigned long start_pfn, end_pfn; |
| unsigned long ret = 0; |
| unsigned long pos; |
| |
| struct map_range mr[NR_RANGE_MR]; |
| int nr_range, i; |
| int use_pse, use_gbpages; |
| |
| printk(KERN_INFO "init_memory_mapping: %016lx-%016lx\n", start, end); |
| |
| if (!after_bootmem) |
| init_gbpages(); |
| |
| #ifdef CONFIG_DEBUG_PAGEALLOC |
| /* |
| * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages. |
| * This will simplify cpa(), which otherwise needs to support splitting |
| * large pages into small in interrupt context, etc. |
| */ |
| use_pse = use_gbpages = 0; |
| #else |
| use_pse = cpu_has_pse; |
| use_gbpages = direct_gbpages; |
| #endif |
| |
| #ifdef CONFIG_X86_32 |
| #ifdef CONFIG_X86_PAE |
| set_nx(); |
| if (nx_enabled) |
| printk(KERN_INFO "NX (Execute Disable) protection: active\n"); |
| #endif |
| |
| /* Enable PSE if available */ |
| if (cpu_has_pse) |
| set_in_cr4(X86_CR4_PSE); |
| |
| /* Enable PGE if available */ |
| if (cpu_has_pge) { |
| set_in_cr4(X86_CR4_PGE); |
| __supported_pte_mask |= _PAGE_GLOBAL; |
| } |
| #endif |
| |
| if (use_gbpages) |
| page_size_mask |= 1 << PG_LEVEL_1G; |
| if (use_pse) |
| page_size_mask |= 1 << PG_LEVEL_2M; |
| |
| memset(mr, 0, sizeof(mr)); |
| nr_range = 0; |
| |
| /* head if not big page alignment ? */ |
| start_pfn = start >> PAGE_SHIFT; |
| pos = start_pfn << PAGE_SHIFT; |
| #ifdef CONFIG_X86_32 |
| /* |
| * Don't use a large page for the first 2/4MB of memory |
| * because there are often fixed size MTRRs in there |
| * and overlapping MTRRs into large pages can cause |
| * slowdowns. |
| */ |
| if (pos == 0) |
| end_pfn = 1<<(PMD_SHIFT - PAGE_SHIFT); |
| else |
| end_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT) |
| << (PMD_SHIFT - PAGE_SHIFT); |
| #else /* CONFIG_X86_64 */ |
| end_pfn = ((pos + (PMD_SIZE - 1)) >> PMD_SHIFT) |
| << (PMD_SHIFT - PAGE_SHIFT); |
| #endif |
| if (end_pfn > (end >> PAGE_SHIFT)) |
| end_pfn = end >> PAGE_SHIFT; |
| if (start_pfn < end_pfn) { |
| nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0); |
| pos = end_pfn << PAGE_SHIFT; |
| } |
| |
| /* big page (2M) range */ |
| start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT) |
| << (PMD_SHIFT - PAGE_SHIFT); |
| #ifdef CONFIG_X86_32 |
| end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT); |
| #else /* CONFIG_X86_64 */ |
| end_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT) |
| << (PUD_SHIFT - PAGE_SHIFT); |
| if (end_pfn > ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT))) |
| end_pfn = ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT)); |
| #endif |
| |
| if (start_pfn < end_pfn) { |
| nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, |
| page_size_mask & (1<<PG_LEVEL_2M)); |
| pos = end_pfn << PAGE_SHIFT; |
| } |
| |
| #ifdef CONFIG_X86_64 |
| /* big page (1G) range */ |
| start_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT) |
| << (PUD_SHIFT - PAGE_SHIFT); |
| end_pfn = (end >> PUD_SHIFT) << (PUD_SHIFT - PAGE_SHIFT); |
| if (start_pfn < end_pfn) { |
| nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, |
| page_size_mask & |
| ((1<<PG_LEVEL_2M)|(1<<PG_LEVEL_1G))); |
| pos = end_pfn << PAGE_SHIFT; |
| } |
| |
| /* tail is not big page (1G) alignment */ |
| start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT) |
| << (PMD_SHIFT - PAGE_SHIFT); |
| end_pfn = (end >> PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT); |
| if (start_pfn < end_pfn) { |
| nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, |
| page_size_mask & (1<<PG_LEVEL_2M)); |
| pos = end_pfn << PAGE_SHIFT; |
| } |
| #endif |
| |
| /* tail is not big page (2M) alignment */ |
| start_pfn = pos>>PAGE_SHIFT; |
| end_pfn = end>>PAGE_SHIFT; |
| nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0); |
| |
| /* try to merge same page size and continuous */ |
| for (i = 0; nr_range > 1 && i < nr_range - 1; i++) { |
| unsigned long old_start; |
| if (mr[i].end != mr[i+1].start || |
| mr[i].page_size_mask != mr[i+1].page_size_mask) |
| continue; |
| /* move it */ |
| old_start = mr[i].start; |
| memmove(&mr[i], &mr[i+1], |
| (nr_range - 1 - i) * sizeof(struct map_range)); |
| mr[i--].start = old_start; |
| nr_range--; |
| } |
| |
| for (i = 0; i < nr_range; i++) |
| printk(KERN_DEBUG " %010lx - %010lx page %s\n", |
| mr[i].start, mr[i].end, |
| (mr[i].page_size_mask & (1<<PG_LEVEL_1G))?"1G":( |
| (mr[i].page_size_mask & (1<<PG_LEVEL_2M))?"2M":"4k")); |
| |
| /* |
| * Find space for the kernel direct mapping tables. |
| * |
| * Later we should allocate these tables in the local node of the |
| * memory mapped. Unfortunately this is done currently before the |
| * nodes are discovered. |
| */ |
| if (!after_bootmem) |
| find_early_table_space(end, use_pse, use_gbpages); |
| |
| #ifdef CONFIG_X86_32 |
| for (i = 0; i < nr_range; i++) |
| kernel_physical_mapping_init(mr[i].start, mr[i].end, |
| mr[i].page_size_mask); |
| ret = end; |
| #else /* CONFIG_X86_64 */ |
| for (i = 0; i < nr_range; i++) |
| ret = kernel_physical_mapping_init(mr[i].start, mr[i].end, |
| mr[i].page_size_mask); |
| #endif |
| |
| #ifdef CONFIG_X86_32 |
| early_ioremap_page_table_range_init(); |
| |
| load_cr3(swapper_pg_dir); |
| #endif |
| |
| #ifdef CONFIG_X86_64 |
| if (!after_bootmem) |
| mmu_cr4_features = read_cr4(); |
| #endif |
| __flush_tlb_all(); |
| |
| if (!after_bootmem && e820_table_end > e820_table_start) |
| reserve_early(e820_table_start << PAGE_SHIFT, |
| e820_table_end << PAGE_SHIFT, "PGTABLE"); |
| |
| if (!after_bootmem) |
| early_memtest(start, end); |
| |
| return ret >> PAGE_SHIFT; |
| } |
| |
| |
| /* |
| * devmem_is_allowed() checks to see if /dev/mem access to a certain address |
| * is valid. The argument is a physical page number. |
| * |
| * |
| * On x86, access has to be given to the first megabyte of ram because that area |
| * contains bios code and data regions used by X and dosemu and similar apps. |
| * Access has to be given to non-kernel-ram areas as well, these contain the PCI |
| * mmio resources as well as potential bios/acpi data regions. |
| */ |
| int devmem_is_allowed(unsigned long pagenr) |
| { |
| if (pagenr <= 256) |
| return 1; |
| if (iomem_is_exclusive(pagenr << PAGE_SHIFT)) |
| return 0; |
| if (!page_is_ram(pagenr)) |
| return 1; |
| return 0; |
| } |
| |
| void free_init_pages(char *what, unsigned long begin, unsigned long end) |
| { |
| unsigned long addr = begin; |
| |
| if (addr >= end) |
| return; |
| |
| /* |
| * If debugging page accesses then do not free this memory but |
| * mark them not present - any buggy init-section access will |
| * create a kernel page fault: |
| */ |
| #ifdef CONFIG_DEBUG_PAGEALLOC |
| printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n", |
| begin, PAGE_ALIGN(end)); |
| set_memory_np(begin, (end - begin) >> PAGE_SHIFT); |
| #else |
| /* |
| * We just marked the kernel text read only above, now that |
| * we are going to free part of that, we need to make that |
| * writeable first. |
| */ |
| set_memory_rw(begin, (end - begin) >> PAGE_SHIFT); |
| |
| printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10); |
| |
| for (; addr < end; addr += PAGE_SIZE) { |
| ClearPageReserved(virt_to_page(addr)); |
| init_page_count(virt_to_page(addr)); |
| memset((void *)(addr & ~(PAGE_SIZE-1)), |
| POISON_FREE_INITMEM, PAGE_SIZE); |
| free_page(addr); |
| totalram_pages++; |
| } |
| #endif |
| } |
| |
| void free_initmem(void) |
| { |
| free_init_pages("unused kernel memory", |
| (unsigned long)(&__init_begin), |
| (unsigned long)(&__init_end)); |
| } |
| |
| #ifdef CONFIG_BLK_DEV_INITRD |
| void free_initrd_mem(unsigned long start, unsigned long end) |
| { |
| free_init_pages("initrd memory", start, end); |
| } |
| #endif |