diff options
Diffstat (limited to 'kernel/arch/arm/mm/init.c')
| -rw-r--r-- | kernel/arch/arm/mm/init.c | 752 |
1 files changed, 752 insertions, 0 deletions
diff --git a/kernel/arch/arm/mm/init.c b/kernel/arch/arm/mm/init.c new file mode 100644 index 000000000..be92fa0f2 --- /dev/null +++ b/kernel/arch/arm/mm/init.c @@ -0,0 +1,752 @@ +/* + * 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 <linux/kernel.h> +#include <linux/errno.h> +#include <linux/swap.h> +#include <linux/init.h> +#include <linux/bootmem.h> +#include <linux/mman.h> +#include <linux/export.h> +#include <linux/nodemask.h> +#include <linux/initrd.h> +#include <linux/of_fdt.h> +#include <linux/highmem.h> +#include <linux/gfp.h> +#include <linux/memblock.h> +#include <linux/dma-contiguous.h> +#include <linux/sizes.h> + +#include <asm/cp15.h> +#include <asm/mach-types.h> +#include <asm/memblock.h> +#include <asm/prom.h> +#include <asm/sections.h> +#include <asm/setup.h> +#include <asm/system_info.h> +#include <asm/tlb.h> +#include <asm/fixmap.h> + +#include <asm/mach/arch.h> +#include <asm/mach/map.h> + +#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) +{ + pr_warn("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); + +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 contiguous allocations */ + 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); + + early_memtest((phys_addr_t)min << PAGE_SHIFT, + (phys_addr_t)max_low << PAGE_SHIFT); + + /* + * 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 +} + +/* + * 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); + +#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) + + pr_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" + " vmalloc : 0x%08lx - 0x%08lx (%4ld MB)\n" + " lowmem : 0x%08lx - 0x%08lx (%4ld MB)\n" +#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" " (%4td kB)\n" + " .init : 0x%p" " - 0x%p" " (%4td kB)\n" + " .data : 0x%p" " - 0x%p" " (%4td kB)\n" + " .bss : 0x%p" " - 0x%p" " (%4td 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), + MLM(VMALLOC_START, VMALLOC_END), + MLM(PAGE_OFFSET, (unsigned long)high_memory), +#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)); + +#undef MLK +#undef MLM +#undef MLK_ROUNDUP + + /* + * 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; + } +} + +#ifdef CONFIG_ARM_KERNMEM_PERMS +struct section_perm { + unsigned long start; + unsigned long end; + pmdval_t mask; + pmdval_t prot; + pmdval_t clear; +}; + +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, + }, + /* Make init RW (set NX). */ + { + .start = (unsigned long)__init_begin, + .end = (unsigned long)_sdata, + .mask = ~PMD_SECT_XN, + .prot = PMD_SECT_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, + }, +#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 + }, +}; +#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(). + */ +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) \ + section_update(addr, perms[i].mask, \ + perms[i].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 |