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/arm26/mm/init.c | 412 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 412 insertions(+) create mode 100644 arch/arm26/mm/init.c (limited to 'arch/arm26/mm/init.c') diff --git a/arch/arm26/mm/init.c b/arch/arm26/mm/init.c new file mode 100644 index 00000000000..1f09a9d0fb8 --- /dev/null +++ b/arch/arm26/mm/init.c @@ -0,0 +1,412 @@ +/* + * linux/arch/arm26/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 + +#include +#include +#include +#include +#include +#include + +#include + + +#define TABLE_SIZE PTRS_PER_PTE * sizeof(pte_t)) + +struct mmu_gather mmu_gathers[NR_CPUS]; + +extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; +extern char _stext, _text, _etext, _end, __init_begin, __init_end; +#ifdef CONFIG_XIP_KERNEL +extern char _endtext, _sdata; +#endif +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; + struct page *page, *end; + + printk("Mem-info:\n"); + show_free_areas(); + printk("Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10)); + + + page = NODE_MEM_MAP(0); + end = page + NODE_DATA(0)->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 PFN_DOWN(x) ((x) >> PAGE_SHIFT) +#define PFN_UP(x) (PAGE_ALIGN(x) >> PAGE_SHIFT) +#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(struct meminfo *mi, unsigned int bootmap_pages) +{ + unsigned int start_pfn, bootmap_pfn; + unsigned int start, end; + + start_pfn = PFN_UP((unsigned long)&_end); + bootmap_pfn = 0; + + /* ARM26 machines only have one node */ + if (mi->bank->node != 0) + BUG(); + + start = PFN_UP(mi->bank->start); + end = PFN_DOWN(mi->bank->size + mi->bank->start); + + if (start < start_pfn) + start = start_pfn; + + if (end <= start) + BUG(); + + if (end - start >= bootmap_pages) + bootmap_pfn = start; + else + 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 void __init +find_memend_and_nodes(struct meminfo *mi, struct node_info *np) +{ + unsigned int memend_pfn = 0; + + nodes_clear(node_online_map); + node_set_online(0); + + np->bootmap_pages = 0; + + if (mi->bank->size == 0) { + BUG(); + } + + /* + * Get the start and end pfns for this bank + */ + np->start = PFN_UP(mi->bank->start); + np->end = PFN_DOWN(mi->bank->start + mi->bank->size); + + if (memend_pfn < np->end) + memend_pfn = np->end; + + /* + * Calculate the number of pages we require to + * store the bootmem bitmaps. + */ + np->bootmap_pages = bootmem_bootmap_pages(np->end - np->start); + + /* + * 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 - PFN_DOWN(PHYS_OFFSET); + max_pfn = memend_pfn - PFN_DOWN(PHYS_OFFSET); + mi->end = memend_pfn << PAGE_SHIFT; + +} + +/* + * Initialise the bootmem allocator for all nodes. This is called + * early during the architecture specific initialisation. + */ +void __init bootmem_init(struct meminfo *mi) +{ + struct node_info node_info; + unsigned int bootmap_pfn; + pg_data_t *pgdat = NODE_DATA(0); + + find_memend_and_nodes(mi, &node_info); + + bootmap_pfn = find_bootmap_pfn(mi, node_info.bootmap_pages); + + /* + * Note that node 0 must always have some pages. + */ + if (node_info.end == 0) + BUG(); + + /* + * Initialise the bootmem allocator. + */ + init_bootmem_node(pgdat, bootmap_pfn, node_info.start, node_info.end); + + /* + * Register all available RAM in this node with the bootmem allocator. + */ + free_bootmem_node(pgdat, mi->bank->start, mi->bank->size); + + /* + * Register the kernel text and data with bootmem. + * Note: with XIP we dont register .text since + * its in ROM. + */ +#ifdef CONFIG_XIP_KERNEL + reserve_bootmem_node(pgdat, __pa(&_sdata), &_end - &_sdata); +#else + reserve_bootmem_node(pgdat, __pa(&_stext), &_end - &_stext); +#endif + + /* + * And don't forget to reserve the allocator bitmap, + * which will be freed later. + */ + reserve_bootmem_node(pgdat, bootmap_pfn << PAGE_SHIFT, + node_info.bootmap_pages << PAGE_SHIFT); + + /* + * These should likewise go elsewhere. They pre-reserve + * the screen memory region at the start of main system + * memory. FIXME - screen RAM is not 512K! + */ + reserve_bootmem_node(pgdat, 0x02000000, 0x00080000); + +#ifdef CONFIG_BLK_DEV_INITRD + initrd_start = phys_initrd_start; + initrd_end = initrd_start + phys_initrd_size; + + /* Achimedes machines only have one node, so initrd is in node 0 */ +#ifdef CONFIG_XIP_KERNEL + /* Only reserve initrd space if it is in RAM */ + if(initrd_start && initrd_start < 0x03000000){ +#else + if(initrd_start){ +#endif + reserve_bootmem_node(pgdat, __pa(initrd_start), + initrd_end - initrd_start); + } +#endif /* CONFIG_BLK_DEV_INITRD */ + + +} + +/* + * 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) +{ + void *zero_page; + unsigned long zone_size[MAX_NR_ZONES]; + unsigned long zhole_size[MAX_NR_ZONES]; + struct bootmem_data *bdata; + pg_data_t *pgdat; + int i; + + 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); + flush_tlb_all(); + + /* + * initialise the zones in node 0 (archimedes have only 1 node) + */ + + for (i = 0; i < MAX_NR_ZONES; i++) { + zone_size[i] = 0; + zhole_size[i] = 0; + } + + pgdat = NODE_DATA(0); + bdata = pgdat->bdata; + zone_size[0] = bdata->node_low_pfn - + (bdata->node_boot_start >> PAGE_SHIFT); + if (!zone_size[0]) + BUG(); + pgdat->node_mem_map = NULL; + free_area_init_node(0, 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); +} + +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; + pg_data_t *pgdat = NODE_DATA(0); + extern int sysctl_overcommit_memory; + + + /* Note: data pages includes BSS */ +#ifdef CONFIG_XIP_KERNEL + codepages = &_endtext - &_text; + datapages = &_end - &_sdata; +#else + codepages = &_etext - &_text; + datapages = &_end - &_etext; +#endif + initpages = &__init_end - &__init_begin; + + high_memory = (void *)__va(meminfo.end); + max_mapnr = virt_to_page(high_memory) - mem_map; + + /* this will put all unused low memory onto the freelists */ + if (pgdat->node_spanned_pages != 0) + totalram_pages += free_all_bootmem_node(pgdat); + + num_physpages = meminfo.bank[0].size >> PAGE_SHIFT; + + printk(KERN_INFO "Memory: %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); + + /* + * Turn on overcommit on tiny machines + */ + if (PAGE_SIZE >= 16384 && num_physpages <= 128) { + sysctl_overcommit_memory = OVERCOMMIT_ALWAYS; + printk("Turning on overcommit\n"); + } +} + +void free_initmem(void){ +#ifndef CONFIG_XIP_KERNEL + free_area((unsigned long)(&__init_begin), + (unsigned long)(&__init_end), + "init"); +#endif +} + +#ifdef CONFIG_BLK_DEV_INITRD + +static int keep_initrd; + +void free_initrd_mem(unsigned long start, unsigned long end) +{ +#ifdef CONFIG_XIP_KERNEL + /* Only bin initrd if it is in RAM... */ + if(!keep_initrd && start < 0x03000000) +#else + if (!keep_initrd) +#endif + 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