/* * linux/arch/arm/mm/init.c * * Copyright (C) 1995-2005 Russell King * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #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.h" #ifdef CONFIG_CPU_CP15_MMU unsigned long __init __clear_cr(unsigned long mask) { cr_alignment = cr_alignment & ~mask; return cr_alignment; } #endif static phys_addr_t phys_initrd_start __initdata = 0; static unsigned long phys_initrd_size __initdata = 0; static int __init early_initrd(char *p) { phys_addr_t start; unsigned long size; char *endp; start = memparse(p, &endp); if (*endp == ',') { size = memparse(endp + 1, NULL); phys_initrd_start = start; phys_initrd_size = size; } return 0; } early_param("initrd", early_initrd); static int __init parse_tag_initrd(const struct tag *tag) { printk(KERN_WARNING "ATAG_INITRD is deprecated; " "please update your bootloader.\n"); phys_initrd_start = __virt_to_phys(tag->u.initrd.start); phys_initrd_size = tag->u.initrd.size; return 0; } __tagtable(ATAG_INITRD, parse_tag_initrd); static int __init parse_tag_initrd2(const struct tag *tag) { phys_initrd_start = tag->u.initrd.start; phys_initrd_size = tag->u.initrd.size; return 0; } __tagtable(ATAG_INITRD2, parse_tag_initrd2); /* * This keeps memory configuration data used by a couple memory * initialization functions, as well as show_mem() for the skipping * of holes in the memory map. It is populated by arm_add_memory(). */ void show_mem(unsigned int filter) { int free = 0, total = 0, reserved = 0; int shared = 0, cached = 0, slab = 0; struct memblock_region *reg; printk("Mem-info:\n"); show_free_areas(filter); for_each_memblock (memory, reg) { unsigned int pfn1, pfn2; struct page *page, *end; pfn1 = memblock_region_memory_base_pfn(reg); pfn2 = memblock_region_memory_end_pfn(reg); page = pfn_to_page(pfn1); end = pfn_to_page(pfn2 - 1) + 1; do { total++; if (PageReserved(page)) reserved++; else if (PageSwapCache(page)) cached++; else if (PageSlab(page)) slab++; else if (!page_count(page)) free++; else shared += page_count(page) - 1; pfn1++; page = pfn_to_page(pfn1); } while (pfn1 < pfn2); } printk("%d pages of RAM\n", total); printk("%d free pages\n", free); printk("%d reserved pages\n", reserved); printk("%d slab pages\n", slab); printk("%d pages shared\n", shared); printk("%d pages swap cached\n", cached); } static void __init find_limits(unsigned long *min, unsigned long *max_low, unsigned long *max_high) { *max_low = PFN_DOWN(memblock_get_current_limit()); *min = PFN_UP(memblock_start_of_DRAM()); *max_high = PFN_DOWN(memblock_end_of_DRAM()); } #ifdef CONFIG_ZONE_DMA phys_addr_t arm_dma_zone_size __read_mostly; EXPORT_SYMBOL(arm_dma_zone_size); /* * The DMA mask corresponding to the maximum bus address allocatable * using GFP_DMA. The default here places no restriction on DMA * allocations. This must be the smallest DMA mask in the system, * so a successful GFP_DMA allocation will always satisfy this. */ phys_addr_t arm_dma_limit; unsigned long arm_dma_pfn_limit; static void __init arm_adjust_dma_zone(unsigned long *size, unsigned long *hole, unsigned long dma_size) { if (size[0] <= dma_size) return; size[ZONE_NORMAL] = size[0] - dma_size; size[ZONE_DMA] = dma_size; hole[ZONE_NORMAL] = hole[0]; hole[ZONE_DMA] = 0; } #endif void __init setup_dma_zone(const struct machine_desc *mdesc) { #ifdef CONFIG_ZONE_DMA if (mdesc->dma_zone_size) { arm_dma_zone_size = mdesc->dma_zone_size; arm_dma_limit = PHYS_OFFSET + arm_dma_zone_size - 1; } else arm_dma_limit = 0xffffffff; arm_dma_pfn_limit = arm_dma_limit >> PAGE_SHIFT; #endif } static void __init zone_sizes_init(unsigned long min, unsigned long max_low, unsigned long max_high) { unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES]; struct memblock_region *reg; /* * initialise the zones. */ memset(zone_size, 0, sizeof(zone_size)); /* * The memory size has already been determined. If we need * to do anything fancy with the allocation of this memory * to the zones, now is the time to do it. */ zone_size[0] = max_low - min; #ifdef CONFIG_HIGHMEM zone_size[ZONE_HIGHMEM] = max_high - max_low; #endif /* * Calculate the size of the holes. * holes = node_size - sum(bank_sizes) */ memcpy(zhole_size, zone_size, sizeof(zhole_size)); for_each_memblock(memory, reg) { unsigned long start = memblock_region_memory_base_pfn(reg); unsigned long end = memblock_region_memory_end_pfn(reg); if (start < max_low) { unsigned long low_end = min(end, max_low); zhole_size[0] -= low_end - start; } #ifdef CONFIG_HIGHMEM if (end > max_low) { unsigned long high_start = max(start, max_low); zhole_size[ZONE_HIGHMEM] -= end - high_start; } #endif } #ifdef CONFIG_ZONE_DMA /* * Adjust the sizes according to any special requirements for * this machine type. */ if (arm_dma_zone_size) arm_adjust_dma_zone(zone_size, zhole_size, arm_dma_zone_size >> PAGE_SHIFT); #endif free_area_init_node(0, zone_size, min, zhole_size); } #ifdef CONFIG_HAVE_ARCH_PFN_VALID int pfn_valid(unsigned long pfn) { return memblock_is_memory(__pfn_to_phys(pfn)); } EXPORT_SYMBOL(pfn_valid); #endif #ifndef CONFIG_SPARSEMEM static void __init arm_memory_present(void) { } #else static void __init arm_memory_present(void) { struct memblock_region *reg; for_each_memblock(memory, reg) memory_present(0, memblock_region_memory_base_pfn(reg), memblock_region_memory_end_pfn(reg)); } #endif static bool arm_memblock_steal_permitted = true; phys_addr_t __init arm_memblock_steal(phys_addr_t size, phys_addr_t align) { phys_addr_t phys; BUG_ON(!arm_memblock_steal_permitted); phys = memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ANYWHERE); memblock_free(phys, size); memblock_remove(phys, size); return phys; } void __init arm_memblock_init(const struct machine_desc *mdesc) { /* Register the kernel text, kernel data and initrd with memblock. */ #ifdef CONFIG_XIP_KERNEL memblock_reserve(__pa(_sdata), _end - _sdata); #else memblock_reserve(__pa(_stext), _end - _stext); #endif #ifdef CONFIG_BLK_DEV_INITRD /* FDT scan will populate initrd_start */ if (initrd_start && !phys_initrd_size) { phys_initrd_start = __virt_to_phys(initrd_start); phys_initrd_size = initrd_end - initrd_start; } initrd_start = initrd_end = 0; if (phys_initrd_size && !memblock_is_region_memory(phys_initrd_start, phys_initrd_size)) { pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region - disabling initrd\n", (u64)phys_initrd_start, phys_initrd_size); phys_initrd_start = phys_initrd_size = 0; } if (phys_initrd_size && memblock_is_region_reserved(phys_initrd_start, phys_initrd_size)) { pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region - disabling initrd\n", (u64)phys_initrd_start, phys_initrd_size); phys_initrd_start = phys_initrd_size = 0; } if (phys_initrd_size) { memblock_reserve(phys_initrd_start, phys_initrd_size); /* Now convert initrd to virtual addresses */ initrd_start = __phys_to_virt(phys_initrd_start); initrd_end = initrd_start + phys_initrd_size; } #endif arm_mm_memblock_reserve(); /* reserve any platform specific memblock areas */ if (mdesc->reserve) mdesc->reserve(); early_init_fdt_scan_reserved_mem(); /* * reserve memory for DMA contigouos allocations, * must come from DMA area inside low memory */ dma_contiguous_reserve(arm_dma_limit); arm_memblock_steal_permitted = false; memblock_dump_all(); } void __init bootmem_init(void) { unsigned long min, max_low, max_high; memblock_allow_resize(); max_low = max_high = 0; find_limits(&min, &max_low, &max_high); /* * Sparsemem tries to allocate bootmem in memory_present(), * so must be done after the fixed reservations */ arm_memory_present(); /* * sparse_init() needs the bootmem allocator up and running. */ sparse_init(); /* * Now free the memory - free_area_init_node needs * the sparse mem_map arrays initialized by sparse_init() * for memmap_init_zone(), otherwise all PFNs are invalid. */ zone_sizes_init(min, max_low, max_high); /* * This doesn't seem to be used by the Linux memory manager any * more, but is used by ll_rw_block. If we can get rid of it, we * also get rid of some of the stuff above as well. */ min_low_pfn = min; max_low_pfn = max_low; max_pfn = max_high; } /* * Poison init memory with an undefined instruction (ARM) or a branch to an * undefined instruction (Thumb). */ static inline void poison_init_mem(void *s, size_t count) { u32 *p = (u32 *)s; for (; count != 0; count -= 4) *p++ = 0xe7fddef0; } static inline void free_memmap(unsigned long start_pfn, unsigned long end_pfn) { struct page *start_pg, *end_pg; phys_addr_t pg, pgend; /* * Convert start_pfn/end_pfn to a struct page pointer. */ start_pg = pfn_to_page(start_pfn - 1) + 1; end_pg = pfn_to_page(end_pfn - 1) + 1; /* * Convert to physical addresses, and * round start upwards and end downwards. */ pg = PAGE_ALIGN(__pa(start_pg)); pgend = __pa(end_pg) & PAGE_MASK; /* * If there are free pages between these, * free the section of the memmap array. */ if (pg < pgend) memblock_free_early(pg, pgend - pg); } /* * The mem_map array can get very big. Free the unused area of the memory map. */ static void __init free_unused_memmap(void) { unsigned long start, prev_end = 0; struct memblock_region *reg; /* * This relies on each bank being in address order. * The banks are sorted previously in bootmem_init(). */ for_each_memblock(memory, reg) { start = memblock_region_memory_base_pfn(reg); #ifdef CONFIG_SPARSEMEM /* * Take care not to free memmap entries that don't exist * due to SPARSEMEM sections which aren't present. */ start = min(start, ALIGN(prev_end, PAGES_PER_SECTION)); #else /* * Align down here since the VM subsystem insists that the * memmap entries are valid from the bank start aligned to * MAX_ORDER_NR_PAGES. */ start = round_down(start, MAX_ORDER_NR_PAGES); #endif /* * If we had a previous bank, and there is a space * between the current bank and the previous, free it. */ if (prev_end && prev_end < start) free_memmap(prev_end, start); /* * Align up here since the VM subsystem insists that the * memmap entries are valid from the bank end aligned to * MAX_ORDER_NR_PAGES. */ prev_end = ALIGN(memblock_region_memory_end_pfn(reg), MAX_ORDER_NR_PAGES); } #ifdef CONFIG_SPARSEMEM if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION)) free_memmap(prev_end, ALIGN(prev_end, PAGES_PER_SECTION)); #endif } #ifdef CONFIG_HIGHMEM static inline void free_area_high(unsigned long pfn, unsigned long end) { for (; pfn < end; pfn++) free_highmem_page(pfn_to_page(pfn)); } #endif static void __init free_highpages(void) { #ifdef CONFIG_HIGHMEM unsigned long max_low = max_low_pfn; struct memblock_region *mem, *res; /* set highmem page free */ for_each_memblock(memory, mem) { unsigned long start = memblock_region_memory_base_pfn(mem); unsigned long end = memblock_region_memory_end_pfn(mem); /* Ignore complete lowmem entries */ if (end <= max_low) continue; /* Truncate partial highmem entries */ if (start < max_low) start = max_low; /* Find and exclude any reserved regions */ for_each_memblock(reserved, res) { unsigned long res_start, res_end; res_start = memblock_region_reserved_base_pfn(res); res_end = memblock_region_reserved_end_pfn(res); if (res_end < start) continue; if (res_start < start) res_start = start; if (res_start > end) res_start = end; if (res_end > end) res_end = end; if (res_start != start) free_area_high(start, res_start); start = res_end; if (start == end) break; } /* And now free anything which remains */ if (start < end) free_area_high(start, end); } #endif } #define MLK(b, t) (b), (t), (((t) - (b)) >> 10) #define MLM(b, t) (b), (t), (((t) - (b)) >> 20) #define MLK_ROUNDUP(b, t) (b), (t), (DIV_ROUND_UP(((t) - (b)), SZ_1K)) #ifdef CONFIG_ENABLE_VMALLOC_SAVING static void print_vmalloc_lowmem_info(void) { struct memblock_region *reg, *prev_reg = NULL; pr_notice( " vmalloc : 0x%08lx - 0x%08lx (%4ld MB)\n", MLM((unsigned long)high_memory, VMALLOC_END)); for_each_memblock_rev(memory, reg) { phys_addr_t start_phys = reg->base; phys_addr_t end_phys = reg->base + reg->size; if (start_phys > arm_lowmem_limit) continue; if (end_phys > arm_lowmem_limit) end_phys = arm_lowmem_limit; if (prev_reg == NULL) { prev_reg = reg; pr_notice( " lowmem : 0x%08lx - 0x%08lx (%4ld MB)\n", MLM((unsigned long)__va(start_phys), (unsigned long)__va(end_phys))); continue; } pr_notice( " vmalloc : 0x%08lx - 0x%08lx (%4ld MB)\n", MLM((unsigned long)__va(end_phys), (unsigned long)__va(prev_reg->base))); pr_notice( " lowmem : 0x%08lx - 0x%08lx (%4ld MB)\n", MLM((unsigned long)__va(start_phys), (unsigned long)__va(end_phys))); } } #endif /* * mem_init() marks the free areas in the mem_map and tells us how much * memory is free. This is done after various parts of the system have * claimed their memory after the kernel image. */ void __init mem_init(void) { #ifdef CONFIG_HAVE_TCM /* These pointers are filled in on TCM detection */ extern u32 dtcm_end; extern u32 itcm_end; #endif set_max_mapnr(pfn_to_page(max_pfn) - mem_map); /* this will put all unused low memory onto the freelists */ free_unused_memmap(); free_all_bootmem(); #ifdef CONFIG_SA1111 /* now that our DMA memory is actually so designated, we can free it */ free_reserved_area(__va(PHYS_OFFSET), swapper_pg_dir, -1, NULL); #endif free_highpages(); mem_init_print_info(NULL); printk(KERN_NOTICE "Virtual kernel memory layout:\n" " vector : 0x%08lx - 0x%08lx (%4ld kB)\n" #ifdef CONFIG_HAVE_TCM " DTCM : 0x%08lx - 0x%08lx (%4ld kB)\n" " ITCM : 0x%08lx - 0x%08lx (%4ld kB)\n" #endif " fixmap : 0x%08lx - 0x%08lx (%4ld kB)\n", MLK(UL(CONFIG_VECTORS_BASE), UL(CONFIG_VECTORS_BASE) + (PAGE_SIZE)), #ifdef CONFIG_HAVE_TCM MLK(DTCM_OFFSET, (unsigned long) dtcm_end), MLK(ITCM_OFFSET, (unsigned long) itcm_end), #endif MLK(FIXADDR_START, FIXADDR_END)); #ifdef CONFIG_ENABLE_VMALLOC_SAVING print_vmalloc_lowmem_info(); #else printk(KERN_NOTICE " vmalloc : 0x%08lx - 0x%08lx (%4ld MB)\n" " lowmem : 0x%08lx - 0x%08lx (%4ld MB)\n", MLM(VMALLOC_START, VMALLOC_END), MLM(PAGE_OFFSET, (unsigned long)high_memory)); #endif printk(KERN_NOTICE #ifdef CONFIG_HIGHMEM " pkmap : 0x%08lx - 0x%08lx (%4ld MB)\n" #endif #ifdef CONFIG_MODULES " modules : 0x%08lx - 0x%08lx (%4ld MB)\n" #endif " .text : 0x%p" " - 0x%p" " (%4d kB)\n" " .init : 0x%p" " - 0x%p" " (%4d kB)\n" " .data : 0x%p" " - 0x%p" " (%4d kB)\n" " .bss : 0x%p" " - 0x%p" " (%4d kB)\n", #ifdef CONFIG_HIGHMEM MLM(PKMAP_BASE, (PKMAP_BASE) + (LAST_PKMAP) * (PAGE_SIZE)), #endif #ifdef CONFIG_MODULES MLM(MODULES_VADDR, MODULES_END), #endif MLK_ROUNDUP(_text, _etext), MLK_ROUNDUP(__init_begin, __init_end), MLK_ROUNDUP(_sdata, _edata), MLK_ROUNDUP(__bss_start, __bss_stop)); /* * Check boundaries twice: Some fundamental inconsistencies can * be detected at build time already. */ #ifdef CONFIG_MMU BUILD_BUG_ON(TASK_SIZE > MODULES_VADDR); BUG_ON(TASK_SIZE > MODULES_VADDR); #endif #ifdef CONFIG_HIGHMEM BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET); BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET); #endif if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) { extern int sysctl_overcommit_memory; /* * On a machine this small we won't get * anywhere without overcommit, so turn * it on by default. */ sysctl_overcommit_memory = OVERCOMMIT_ALWAYS; } } #undef MLK #undef MLM #undef MLK_ROUNDUP #ifdef CONFIG_ARM_KERNMEM_PERMS struct section_perm { unsigned long start; unsigned long end; pmdval_t mask; pmdval_t prot; pmdval_t clear; pteval_t ptemask; pteval_t pteprot; pteval_t pteclear; }; static struct section_perm nx_perms[] = { /* Make pages tables, etc before _stext RW (set NX). */ { .start = PAGE_OFFSET, .end = (unsigned long)_stext, .mask = ~PMD_SECT_XN, .prot = PMD_SECT_XN, .ptemask = ~L_PTE_XN, .pteprot = L_PTE_XN, }, /* Make init RW (set NX). */ { .start = (unsigned long)__init_begin, .end = (unsigned long)_sdata, .mask = ~PMD_SECT_XN, .prot = PMD_SECT_XN, .ptemask = ~L_PTE_XN, .pteprot = L_PTE_XN, }, #ifdef CONFIG_DEBUG_RODATA /* Make rodata NX (set RO in ro_perms below). */ { .start = (unsigned long)__start_rodata, .end = (unsigned long)__init_begin, .mask = ~PMD_SECT_XN, .prot = PMD_SECT_XN, .ptemask = ~L_PTE_XN, .pteprot = L_PTE_XN, }, #endif }; #ifdef CONFIG_DEBUG_RODATA static struct section_perm ro_perms[] = { /* Make kernel code and rodata RX (set RO). */ { .start = (unsigned long)_stext, .end = (unsigned long)__init_begin, #ifdef CONFIG_ARM_LPAE .mask = ~L_PMD_SECT_RDONLY, .prot = L_PMD_SECT_RDONLY, #else .mask = ~(PMD_SECT_APX | PMD_SECT_AP_WRITE), .prot = PMD_SECT_APX | PMD_SECT_AP_WRITE, .clear = PMD_SECT_AP_WRITE, #endif .ptemask = ~L_PTE_RDONLY, .pteprot = L_PTE_RDONLY, }, }; #endif /* * Updates section permissions only for the current mm (sections are * copied into each mm). During startup, this is the init_mm. Is only * safe to be called with preemption disabled, as under stop_machine(). */ struct pte_data { pteval_t mask; pteval_t val; }; static int __pte_update(pte_t *ptep, pgtable_t token, unsigned long addr, void *d) { struct pte_data *data = d; pte_t pte = *ptep; pte = __pte((pte_val(*ptep) & data->mask) | data->val); set_pte_ext(ptep, pte, 0); return 0; } static inline void pte_update(unsigned long addr, pteval_t mask, pteval_t prot) { struct pte_data data; struct mm_struct *mm; data.mask = mask; data.val = prot; mm = current->active_mm; apply_to_page_range(mm, addr, SECTION_SIZE, __pte_update, &data); flush_tlb_kernel_range(addr, addr + SECTION_SIZE); } static inline void section_update(unsigned long addr, pmdval_t mask, pmdval_t prot) { struct mm_struct *mm; pmd_t *pmd; mm = current->active_mm; pmd = pmd_offset(pud_offset(pgd_offset(mm, addr), addr), addr); #ifdef CONFIG_ARM_LPAE pmd[0] = __pmd((pmd_val(pmd[0]) & mask) | prot); #else if (addr & SECTION_SIZE) pmd[1] = __pmd((pmd_val(pmd[1]) & mask) | prot); else pmd[0] = __pmd((pmd_val(pmd[0]) & mask) | prot); #endif flush_pmd_entry(pmd); local_flush_tlb_kernel_range(addr, addr + SECTION_SIZE); } /* Make sure extended page tables are in use. */ static inline bool arch_has_strict_perms(void) { if (cpu_architecture() < CPU_ARCH_ARMv6) return false; return !!(get_cr() & CR_XP); } #define set_section_perms(perms, field) { \ size_t i; \ unsigned long addr; \ \ if (!arch_has_strict_perms()) \ return; \ \ for (i = 0; i < ARRAY_SIZE(perms); i++) { \ if (!IS_ALIGNED(perms[i].start, SECTION_SIZE) || \ !IS_ALIGNED(perms[i].end, SECTION_SIZE)) { \ pr_err("BUG: section %lx-%lx not aligned to %lx\n", \ perms[i].start, perms[i].end, \ SECTION_SIZE); \ continue; \ } \ \ for (addr = perms[i].start; \ addr < perms[i].end; \ addr += SECTION_SIZE) { \ pmd_t *pmd; \ struct mm_struct *mm; \ \ mm = current->active_mm; \ pmd = pmd_offset(pud_offset(pgd_offset(mm, addr), \ addr), addr); \ if (pmd_bad(*pmd)) \ section_update(addr, perms[i].mask, \ perms[i].field); \ else \ pte_update(addr, perms[i].ptemask, \ perms[i].pte##field); \ } \ } \ } static inline void fix_kernmem_perms(void) { set_section_perms(nx_perms, prot); } #ifdef CONFIG_DEBUG_RODATA void mark_rodata_ro(void) { set_section_perms(ro_perms, prot); } void set_kernel_text_rw(void) { set_section_perms(ro_perms, clear); } void set_kernel_text_ro(void) { set_section_perms(ro_perms, prot); } #endif /* CONFIG_DEBUG_RODATA */ #else static inline void fix_kernmem_perms(void) { } #endif /* CONFIG_ARM_KERNMEM_PERMS */ void free_tcmmem(void) { #ifdef CONFIG_HAVE_TCM extern char __tcm_start, __tcm_end; poison_init_mem(&__tcm_start, &__tcm_end - &__tcm_start); free_reserved_area(&__tcm_start, &__tcm_end, -1, "TCM link"); #endif } void free_initmem(void) { fix_kernmem_perms(); free_tcmmem(); poison_init_mem(__init_begin, __init_end - __init_begin); if (!machine_is_integrator() && !machine_is_cintegrator()) free_initmem_default(-1); } #ifdef CONFIG_BLK_DEV_INITRD static int keep_initrd; void free_initrd_mem(unsigned long start, unsigned long end) { if (!keep_initrd) { if (start == initrd_start) start = round_down(start, PAGE_SIZE); if (end == initrd_end) end = round_up(end, PAGE_SIZE); poison_init_mem((void *)start, PAGE_ALIGN(end) - start); free_reserved_area((void *)start, (void *)end, -1, "initrd"); } } static int __init keepinitrd_setup(char *__unused) { keep_initrd = 1; return 1; } __setup("keepinitrd", keepinitrd_setup); #endif