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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/arm/mm/init.c
downloadlinux-stericsson-2.6.12-rc2.tar.gz
Linux-2.6.12-rc2v2.6.12-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!
Diffstat (limited to 'arch/arm/mm/init.c')
-rw-r--r--arch/arm/mm/init.c621
1 files changed, 621 insertions, 0 deletions
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 <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/swap.h>
+#include <linux/init.h>
+#include <linux/bootmem.h>
+#include <linux/mman.h>
+#include <linux/nodemask.h>
+#include <linux/initrd.h>
+
+#include <asm/mach-types.h>
+#include <asm/hardware.h>
+#include <asm/setup.h>
+#include <asm/tlb.h>
+
+#include <asm/mach/arch.h>
+#include <asm/mach/map.h>
+
+#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