arch/powerpc/mm/init_64.c

   1 /*
   2  *  PowerPC version
   3  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
   4  *
   5  *  Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
   6  *  and Cort Dougan (PReP) (cort@cs.nmt.edu)
   7  *    Copyright (C) 1996 Paul Mackerras
   8  *
   9  *  Derived from "arch/i386/mm/init.c"
  10  *    Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
  11  *
  12  *  Dave Engebretsen <engebret@us.ibm.com>
  13  *      Rework for PPC64 port.
  14  *
  15  *  This program is free software; you can redistribute it and/or
  16  *  modify it under the terms of the GNU General Public License
  17  *  as published by the Free Software Foundation; either version
  18  *  2 of the License, or (at your option) any later version.
  19  *
  20  */
  21
  22 #undef DEBUG
  23
  24 #include <linux/signal.h>
  25 #include <linux/sched.h>
  26 #include <linux/kernel.h>
  27 #include <linux/errno.h>
  28 #include <linux/string.h>
  29 #include <linux/types.h>
  30 #include <linux/mman.h>
  31 #include <linux/mm.h>
  32 #include <linux/swap.h>
  33 #include <linux/stddef.h>
  34 #include <linux/vmalloc.h>
  35 #include <linux/init.h>
  36 #include <linux/delay.h>
  37 #include <linux/bootmem.h>
  38 #include <linux/highmem.h>
  39 #include <linux/idr.h>
  40 #include <linux/nodemask.h>
  41 #include <linux/module.h>
  42 #include <linux/poison.h>
  43 #include <linux/lmb.h>
  44
  45 #include <asm/pgalloc.h>
  46 #include <asm/page.h>
  47 #include <asm/prom.h>
  48 #include <asm/rtas.h>
  49 #include <asm/io.h>
  50 #include <asm/mmu_context.h>
  51 #include <asm/pgtable.h>
  52 #include <asm/mmu.h>
  53 #include <asm/uaccess.h>
  54 #include <asm/smp.h>
  55 #include <asm/machdep.h>
  56 #include <asm/tlb.h>
  57 #include <asm/eeh.h>
  58 #include <asm/processor.h>
  59 #include <asm/mmzone.h>
  60 #include <asm/cputable.h>
  61 #include <asm/sections.h>
  62 #include <asm/system.h>
  63 #include <asm/iommu.h>
  64 #include <asm/abs_addr.h>
  65 #include <asm/vdso.h>
  66
  67 #include "mmu_decl.h"
  68
  69 #if PGTABLE_RANGE > USER_VSID_RANGE
  70 #warning Limited user VSID range means pagetable space is wasted
  71 #endif
  72
  73 #if (TASK_SIZE_USER64 < PGTABLE_RANGE) && (TASK_SIZE_USER64 < USER_VSID_RANGE)
  74 #warning TASK_SIZE is smaller than it needs to be.
  75 #endif
  76
  77 phys_addr_t memstart_addr = ~0;
  78 phys_addr_t kernstart_addr;
  79
  80 void free_initmem(void)
  81 {
  82         unsigned long addr;
  83
  84         addr = (unsigned long)__init_begin;
  85         for (; addr < (unsigned long)__init_end; addr += PAGE_SIZE) {
  86                 memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
  87                 ClearPageReserved(virt_to_page(addr));
  88                 init_page_count(virt_to_page(addr));
  89                 free_page(addr);
  90                 totalram_pages++;
  91         }
  92         printk ("Freeing unused kernel memory: %luk freed\n",
  93                 ((unsigned long)__init_end - (unsigned long)__init_begin) >> 10);
  94 }
  95
  96 #ifdef CONFIG_BLK_DEV_INITRD
  97 void free_initrd_mem(unsigned long start, unsigned long end)
  98 {
  99         if (start < end)
 100                 printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
 101         for (; start < end; start += PAGE_SIZE) {
 102                 ClearPageReserved(virt_to_page(start));
 103                 init_page_count(virt_to_page(start));
 104                 free_page(start);
 105                 totalram_pages++;
 106         }
 107 }
 108 #endif
 109
 110 #ifdef CONFIG_PROC_KCORE
 111 static struct kcore_list kcore_vmem;
 112
 113 static int __init setup_kcore(void)
 114 {
 115         int i;
 116
 117         for (i=0; i < lmb.memory.cnt; i++) {
 118                 unsigned long base, size;
 119                 struct kcore_list *kcore_mem;
 120
 121                 base = lmb.memory.region[i].base;
 122                 size = lmb.memory.region[i].size;
 123
 124                 /* GFP_ATOMIC to avoid might_sleep warnings during boot */
 125                 kcore_mem = kmalloc(sizeof(struct kcore_list), GFP_ATOMIC);
 126                 if (!kcore_mem)
 127                         panic("%s: kmalloc failed\n", __func__);
 128
 129                 kclist_add(kcore_mem, __va(base), size);
 130         }
 131
 132         kclist_add(&kcore_vmem, (void *)VMALLOC_START, VMALLOC_END-VMALLOC_START);
 133
 134         return 0;
 135 }
 136 module_init(setup_kcore);
 137 #endif
 138
 139 static void pgd_ctor(void *addr)
 140 {
 141         memset(addr, 0, PGD_TABLE_SIZE);
 142 }
 143
 144 static void pmd_ctor(void *addr)
 145 {
 146         memset(addr, 0, PMD_TABLE_SIZE);
 147 }
 148
 149 static const unsigned int pgtable_cache_size[2] = {
 150         PGD_TABLE_SIZE, PMD_TABLE_SIZE
 151 };
 152 static const char *pgtable_cache_name[ARRAY_SIZE(pgtable_cache_size)] = {
 153 #ifdef CONFIG_PPC_64K_PAGES
 154         "pgd_cache", "pmd_cache",
 155 #else
 156         "pgd_cache", "pud_pmd_cache",
 157 #endif /* CONFIG_PPC_64K_PAGES */
 158 };
 159
 160 #ifdef CONFIG_HUGETLB_PAGE
 161 /* Hugepages need an extra cache per hugepagesize, initialized in
 162  * hugetlbpage.c.  We can't put into the tables above, because HPAGE_SHIFT
 163  * is not compile time constant. */
 164 struct kmem_cache *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)+MMU_PAGE_COUNT];
 165 #else
 166 struct kmem_cache *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)];
 167 #endif
 168
 169 void pgtable_cache_init(void)
 170 {
 171         pgtable_cache[0] = kmem_cache_create(pgtable_cache_name[0], PGD_TABLE_SIZE, PGD_TABLE_SIZE, SLAB_PANIC, pgd_ctor);
 172         pgtable_cache[1] = kmem_cache_create(pgtable_cache_name[1], PMD_TABLE_SIZE, PMD_TABLE_SIZE, SLAB_PANIC, pmd_ctor);
 173 }
 174
 175 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 176 /*
 177  * Given an address within the vmemmap, determine the pfn of the page that
 178  * represents the start of the section it is within.  Note that we have to
 179  * do this by hand as the proffered address may not be correctly aligned.
 180  * Subtraction of non-aligned pointers produces undefined results.
 181  */
 182 static unsigned long __meminit vmemmap_section_start(unsigned long page)
 183 {
 184         unsigned long offset = page - ((unsigned long)(vmemmap));
 185
 186         /* Return the pfn of the start of the section. */
 187         return (offset / sizeof(struct page)) & PAGE_SECTION_MASK;
 188 }
 189
 190 /*
 191  * Check if this vmemmap page is already initialised.  If any section
 192  * which overlaps this vmemmap page is initialised then this page is
 193  * initialised already.
 194  */
 195 static int __meminit vmemmap_populated(unsigned long start, int page_size)
 196 {
 197         unsigned long end = start + page_size;
 198
 199         for (; start < end; start += (PAGES_PER_SECTION * sizeof(struct page)))
 200                 if (pfn_valid(vmemmap_section_start(start)))
 201                         return 1;
 202
 203         return 0;
 204 }
 205
 206 int __meminit vmemmap_populate(struct page *start_page,
 207                                unsigned long nr_pages, int node)
 208 {
 209         unsigned long start = (unsigned long)start_page;
 210         unsigned long end = (unsigned long)(start_page + nr_pages);
 211         unsigned long page_size = 1 << mmu_psize_defs[mmu_vmemmap_psize].shift;
 212
 213         /* Align to the page size of the linear mapping. */
 214         start = _ALIGN_DOWN(start, page_size);
 215
 216         for (; start < end; start += page_size) {
 217                 int mapped;
 218                 void *p;
 219
 220                 if (vmemmap_populated(start, page_size))
 221                         continue;
 222
 223                 p = vmemmap_alloc_block(page_size, node);
 224                 if (!p)
 225                         return -ENOMEM;
 226
 227                 pr_debug("vmemmap %08lx allocated at %p, physical %08lx.\n",
 228                         start, p, __pa(p));
 229
 230                 mapped = htab_bolt_mapping(start, start + page_size, __pa(p),
 231                                            pgprot_val(PAGE_KERNEL),
 232                                            mmu_vmemmap_psize, mmu_kernel_ssize);
 233                 BUG_ON(mapped < 0);
 234         }
 235
 236         return 0;
 237 }
 238 #endif /* CONFIG_SPARSEMEM_VMEMMAP */