From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 16 Apr 2005 15:20:36 -0700 Subject: Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip! --- arch/arm/mm/init.c | 621 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 621 insertions(+) create mode 100644 arch/arm/mm/init.c (limited to 'arch/arm/mm/init.c') diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c new file mode 100644 index 000000000000..41156c5370f7 --- /dev/null +++ b/arch/arm/mm/init.c @@ -0,0 +1,621 @@ +/* + * linux/arch/arm/mm/init.c + * + * Copyright (C) 1995-2002 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 + +#define TABLE_SIZE (2 * PTRS_PER_PTE * sizeof(pte_t)) + +DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); + +extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; +extern void _stext, _text, _etext, __data_start, _end, __init_begin, __init_end; +extern unsigned long phys_initrd_start; +extern unsigned long phys_initrd_size; + +/* + * The sole use of this is to pass memory configuration + * data from paging_init to mem_init. + */ +static struct meminfo meminfo __initdata = { 0, }; + +/* + * empty_zero_page is a special page that is used for + * zero-initialized data and COW. + */ +struct page *empty_zero_page; + +void show_mem(void) +{ + int free = 0, total = 0, reserved = 0; + int shared = 0, cached = 0, slab = 0, node; + + printk("Mem-info:\n"); + show_free_areas(); + printk("Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10)); + + for_each_online_node(node) { + struct page *page, *end; + + page = NODE_MEM_MAP(node); + end = page + NODE_DATA(node)->node_spanned_pages; + + 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; + page++; + } while (page < end); + } + + 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); +} + +struct node_info { + unsigned int start; + unsigned int end; + int bootmap_pages; +}; + +#define O_PFN_DOWN(x) ((x) >> PAGE_SHIFT) +#define V_PFN_DOWN(x) O_PFN_DOWN(__pa(x)) + +#define O_PFN_UP(x) (PAGE_ALIGN(x) >> PAGE_SHIFT) +#define V_PFN_UP(x) O_PFN_UP(__pa(x)) + +#define PFN_SIZE(x) ((x) >> PAGE_SHIFT) +#define PFN_RANGE(s,e) PFN_SIZE(PAGE_ALIGN((unsigned long)(e)) - \ + (((unsigned long)(s)) & PAGE_MASK)) + +/* + * FIXME: We really want to avoid allocating the bootmap bitmap + * over the top of the initrd. Hopefully, this is located towards + * the start of a bank, so if we allocate the bootmap bitmap at + * the end, we won't clash. + */ +static unsigned int __init +find_bootmap_pfn(int node, struct meminfo *mi, unsigned int bootmap_pages) +{ + unsigned int start_pfn, bank, bootmap_pfn; + + start_pfn = V_PFN_UP(&_end); + bootmap_pfn = 0; + + for (bank = 0; bank < mi->nr_banks; bank ++) { + unsigned int start, end; + + if (mi->bank[bank].node != node) + continue; + + start = O_PFN_UP(mi->bank[bank].start); + end = O_PFN_DOWN(mi->bank[bank].size + + mi->bank[bank].start); + + if (end < start_pfn) + continue; + + if (start < start_pfn) + start = start_pfn; + + if (end <= start) + continue; + + if (end - start >= bootmap_pages) { + bootmap_pfn = start; + break; + } + } + + if (bootmap_pfn == 0) + BUG(); + + return bootmap_pfn; +} + +/* + * Scan the memory info structure and pull out: + * - the end of memory + * - the number of nodes + * - the pfn range of each node + * - the number of bootmem bitmap pages + */ +static unsigned int __init +find_memend_and_nodes(struct meminfo *mi, struct node_info *np) +{ + unsigned int i, bootmem_pages = 0, memend_pfn = 0; + + for (i = 0; i < MAX_NUMNODES; i++) { + np[i].start = -1U; + np[i].end = 0; + np[i].bootmap_pages = 0; + } + + for (i = 0; i < mi->nr_banks; i++) { + unsigned long start, end; + int node; + + if (mi->bank[i].size == 0) { + /* + * Mark this bank with an invalid node number + */ + mi->bank[i].node = -1; + continue; + } + + node = mi->bank[i].node; + + /* + * Make sure we haven't exceeded the maximum number of nodes + * that we have in this configuration. If we have, we're in + * trouble. (maybe we ought to limit, instead of bugging?) + */ + if (node >= MAX_NUMNODES) + BUG(); + node_set_online(node); + + /* + * Get the start and end pfns for this bank + */ + start = O_PFN_UP(mi->bank[i].start); + end = O_PFN_DOWN(mi->bank[i].start + mi->bank[i].size); + + if (np[node].start > start) + np[node].start = start; + + if (np[node].end < end) + np[node].end = end; + + if (memend_pfn < end) + memend_pfn = end; + } + + /* + * Calculate the number of pages we require to + * store the bootmem bitmaps. + */ + for_each_online_node(i) { + if (np[i].end == 0) + continue; + + np[i].bootmap_pages = bootmem_bootmap_pages(np[i].end - + np[i].start); + bootmem_pages += np[i].bootmap_pages; + } + + high_memory = __va(memend_pfn << PAGE_SHIFT); + + /* + * This doesn't seem to be used by the Linux memory + * manager any more. If we can get rid of it, we + * also get rid of some of the stuff above as well. + */ + max_low_pfn = memend_pfn - O_PFN_DOWN(PHYS_OFFSET); + max_pfn = memend_pfn - O_PFN_DOWN(PHYS_OFFSET); + + return bootmem_pages; +} + +static int __init check_initrd(struct meminfo *mi) +{ + int initrd_node = -2; +#ifdef CONFIG_BLK_DEV_INITRD + unsigned long end = phys_initrd_start + phys_initrd_size; + + /* + * Make sure that the initrd is within a valid area of + * memory. + */ + if (phys_initrd_size) { + unsigned int i; + + initrd_node = -1; + + for (i = 0; i < mi->nr_banks; i++) { + unsigned long bank_end; + + bank_end = mi->bank[i].start + mi->bank[i].size; + + if (mi->bank[i].start <= phys_initrd_start && + end <= bank_end) + initrd_node = mi->bank[i].node; + } + } + + if (initrd_node == -1) { + printk(KERN_ERR "initrd (0x%08lx - 0x%08lx) extends beyond " + "physical memory - disabling initrd\n", + phys_initrd_start, end); + phys_initrd_start = phys_initrd_size = 0; + } +#endif + + return initrd_node; +} + +/* + * Reserve the various regions of node 0 + */ +static __init void reserve_node_zero(unsigned int bootmap_pfn, unsigned int bootmap_pages) +{ + pg_data_t *pgdat = NODE_DATA(0); + unsigned long res_size = 0; + + /* + * Register the kernel text and data with bootmem. + * Note that this can only be in node 0. + */ +#ifdef CONFIG_XIP_KERNEL + reserve_bootmem_node(pgdat, __pa(&__data_start), &_end - &__data_start); +#else + reserve_bootmem_node(pgdat, __pa(&_stext), &_end - &_stext); +#endif + + /* + * Reserve the page tables. These are already in use, + * and can only be in node 0. + */ + reserve_bootmem_node(pgdat, __pa(swapper_pg_dir), + PTRS_PER_PGD * sizeof(pgd_t)); + + /* + * And don't forget to reserve the allocator bitmap, + * which will be freed later. + */ + reserve_bootmem_node(pgdat, bootmap_pfn << PAGE_SHIFT, + bootmap_pages << PAGE_SHIFT); + + /* + * Hmm... This should go elsewhere, but we really really need to + * stop things allocating the low memory; ideally we need a better + * implementation of GFP_DMA which does not assume that DMA-able + * memory starts at zero. + */ + if (machine_is_integrator() || machine_is_cintegrator()) + res_size = __pa(swapper_pg_dir) - PHYS_OFFSET; + + /* + * These should likewise go elsewhere. They pre-reserve the + * screen memory region at the start of main system memory. + */ + if (machine_is_edb7211()) + res_size = 0x00020000; + if (machine_is_p720t()) + res_size = 0x00014000; + +#ifdef CONFIG_SA1111 + /* + * Because of the SA1111 DMA bug, we want to preserve our + * precious DMA-able memory... + */ + res_size = __pa(swapper_pg_dir) - PHYS_OFFSET; +#endif + if (res_size) + reserve_bootmem_node(pgdat, PHYS_OFFSET, res_size); +} + +/* + * Register all available RAM in this node with the bootmem allocator. + */ +static inline void free_bootmem_node_bank(int node, struct meminfo *mi) +{ + pg_data_t *pgdat = NODE_DATA(node); + int bank; + + for (bank = 0; bank < mi->nr_banks; bank++) + if (mi->bank[bank].node == node) + free_bootmem_node(pgdat, mi->bank[bank].start, + mi->bank[bank].size); +} + +/* + * Initialise the bootmem allocator for all nodes. This is called + * early during the architecture specific initialisation. + */ +static void __init bootmem_init(struct meminfo *mi) +{ + struct node_info node_info[MAX_NUMNODES], *np = node_info; + unsigned int bootmap_pages, bootmap_pfn, map_pg; + int node, initrd_node; + + bootmap_pages = find_memend_and_nodes(mi, np); + bootmap_pfn = find_bootmap_pfn(0, mi, bootmap_pages); + initrd_node = check_initrd(mi); + + map_pg = bootmap_pfn; + + /* + * Initialise the bootmem nodes. + * + * What we really want to do is: + * + * unmap_all_regions_except_kernel(); + * for_each_node_in_reverse_order(node) { + * map_node(node); + * allocate_bootmem_map(node); + * init_bootmem_node(node); + * free_bootmem_node(node); + * } + * + * but this is a 2.5-type change. For now, we just set + * the nodes up in reverse order. + * + * (we could also do with rolling bootmem_init and paging_init + * into one generic "memory_init" type function). + */ + np += num_online_nodes() - 1; + for (node = num_online_nodes() - 1; node >= 0; node--, np--) { + /* + * If there are no pages in this node, ignore it. + * Note that node 0 must always have some pages. + */ + if (np->end == 0 || !node_online(node)) { + if (node == 0) + BUG(); + continue; + } + + /* + * Initialise the bootmem allocator. + */ + init_bootmem_node(NODE_DATA(node), map_pg, np->start, np->end); + free_bootmem_node_bank(node, mi); + map_pg += np->bootmap_pages; + + /* + * If this is node 0, we need to reserve some areas ASAP - + * we may use bootmem on node 0 to setup the other nodes. + */ + if (node == 0) + reserve_node_zero(bootmap_pfn, bootmap_pages); + } + + +#ifdef CONFIG_BLK_DEV_INITRD + if (phys_initrd_size && initrd_node >= 0) { + reserve_bootmem_node(NODE_DATA(initrd_node), phys_initrd_start, + phys_initrd_size); + initrd_start = __phys_to_virt(phys_initrd_start); + initrd_end = initrd_start + phys_initrd_size; + } +#endif + + BUG_ON(map_pg != bootmap_pfn + bootmap_pages); +} + +/* + * paging_init() sets up the page tables, initialises the zone memory + * maps, and sets up the zero page, bad page and bad page tables. + */ +void __init paging_init(struct meminfo *mi, struct machine_desc *mdesc) +{ + void *zero_page; + int node; + + bootmem_init(mi); + + memcpy(&meminfo, mi, sizeof(meminfo)); + + /* + * allocate the zero page. Note that we count on this going ok. + */ + zero_page = alloc_bootmem_low_pages(PAGE_SIZE); + + /* + * initialise the page tables. + */ + memtable_init(mi); + if (mdesc->map_io) + mdesc->map_io(); + flush_tlb_all(); + + /* + * initialise the zones within each node + */ + for_each_online_node(node) { + unsigned long zone_size[MAX_NR_ZONES]; + unsigned long zhole_size[MAX_NR_ZONES]; + struct bootmem_data *bdata; + pg_data_t *pgdat; + int i; + + /* + * Initialise the zone size information. + */ + for (i = 0; i < MAX_NR_ZONES; i++) { + zone_size[i] = 0; + zhole_size[i] = 0; + } + + pgdat = NODE_DATA(node); + bdata = pgdat->bdata; + + /* + * The size of this node 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] = bdata->node_low_pfn - + (bdata->node_boot_start >> PAGE_SHIFT); + + /* + * If this zone has zero size, skip it. + */ + if (!zone_size[0]) + continue; + + /* + * For each bank in this node, calculate the size of the + * holes. holes = node_size - sum(bank_sizes_in_node) + */ + zhole_size[0] = zone_size[0]; + for (i = 0; i < mi->nr_banks; i++) { + if (mi->bank[i].node != node) + continue; + + zhole_size[0] -= mi->bank[i].size >> PAGE_SHIFT; + } + + /* + * Adjust the sizes according to any special + * requirements for this machine type. + */ + arch_adjust_zones(node, zone_size, zhole_size); + + free_area_init_node(node, pgdat, zone_size, + bdata->node_boot_start >> PAGE_SHIFT, zhole_size); + } + + /* + * finish off the bad pages once + * the mem_map is initialised + */ + memzero(zero_page, PAGE_SIZE); + empty_zero_page = virt_to_page(zero_page); + flush_dcache_page(empty_zero_page); +} + +static inline void free_area(unsigned long addr, unsigned long end, char *s) +{ + unsigned int size = (end - addr) >> 10; + + for (; addr < end; addr += PAGE_SIZE) { + struct page *page = virt_to_page(addr); + ClearPageReserved(page); + set_page_count(page, 1); + free_page(addr); + totalram_pages++; + } + + if (size && s) + printk(KERN_INFO "Freeing %s memory: %dK\n", s, size); +} + +/* + * 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) +{ + unsigned int codepages, datapages, initpages; + int i, node; + + codepages = &_etext - &_text; + datapages = &_end - &__data_start; + initpages = &__init_end - &__init_begin; + +#ifndef CONFIG_DISCONTIGMEM + max_mapnr = virt_to_page(high_memory) - mem_map; +#endif + + /* + * We may have non-contiguous memory. + */ + if (meminfo.nr_banks != 1) + create_memmap_holes(&meminfo); + + /* this will put all unused low memory onto the freelists */ + for_each_online_node(node) { + pg_data_t *pgdat = NODE_DATA(node); + + if (pgdat->node_spanned_pages != 0) + totalram_pages += free_all_bootmem_node(pgdat); + } + +#ifdef CONFIG_SA1111 + /* now that our DMA memory is actually so designated, we can free it */ + free_area(PAGE_OFFSET, (unsigned long)swapper_pg_dir, NULL); +#endif + + /* + * Since our memory may not be contiguous, calculate the + * real number of pages we have in this system + */ + printk(KERN_INFO "Memory:"); + + num_physpages = 0; + for (i = 0; i < meminfo.nr_banks; i++) { + num_physpages += meminfo.bank[i].size >> PAGE_SHIFT; + printk(" %ldMB", meminfo.bank[i].size >> 20); + } + + printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT)); + printk(KERN_NOTICE "Memory: %luKB available (%dK code, " + "%dK data, %dK init)\n", + (unsigned long) nr_free_pages() << (PAGE_SHIFT-10), + codepages >> 10, datapages >> 10, initpages >> 10); + + if (PAGE_SIZE >= 16384 && 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; + } +} + +void free_initmem(void) +{ + if (!machine_is_integrator() && !machine_is_cintegrator()) { + free_area((unsigned long)(&__init_begin), + (unsigned long)(&__init_end), + "init"); + } +} + +#ifdef CONFIG_BLK_DEV_INITRD + +static int keep_initrd; + +void free_initrd_mem(unsigned long start, unsigned long end) +{ + if (!keep_initrd) + free_area(start, end, "initrd"); +} + +static int __init keepinitrd_setup(char *__unused) +{ + keep_initrd = 1; + return 1; +} + +__setup("keepinitrd", keepinitrd_setup); +#endif -- cgit v1.2.3-59-g8ed1b