arch/sh/mm/init.c

   1 /*
   2  * linux/arch/sh/mm/init.c
   3  *
   4  *  Copyright (C) 1999  Niibe Yutaka
   5  *  Copyright (C) 2002 - 2007  Paul Mundt
   6  *
   7  *  Based on linux/arch/i386/mm/init.c:
   8  *   Copyright (C) 1995  Linus Torvalds
   9  */
  10 #include <linux/mm.h>
  11 #include <linux/swap.h>
  12 #include <linux/init.h>
  13 #include <linux/bootmem.h>
  14 #include <linux/proc_fs.h>
  15 #include <linux/pagemap.h>
  16 #include <linux/percpu.h>
  17 #include <linux/io.h>
  18 #include <asm/mmu_context.h>
  19 #include <asm/tlb.h>
  20 #include <asm/cacheflush.h>
  21 #include <asm/sections.h>
  22 #include <asm/cache.h>
  23
  24 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
  25 pgd_t swapper_pg_dir[PTRS_PER_PGD];
  26
  27 void show_mem(void)
  28 {
  29         int total = 0, reserved = 0, free = 0;
  30         int shared = 0, cached = 0, slab = 0;
  31         pg_data_t *pgdat;
  32
  33         printk("Mem-info:\n");
  34         show_free_areas();
  35
  36         for_each_online_pgdat(pgdat) {
  37                 unsigned long flags, i;
  38
  39                 pgdat_resize_lock(pgdat, &flags);
  40                 for (i = 0; i < pgdat->node_spanned_pages; i++) {
  41                         struct page *page = pgdat_page_nr(pgdat, i);
  42                         total++;
  43                         if (PageReserved(page))
  44                                 reserved++;
  45                         else if (PageSwapCache(page))
  46                                 cached++;
  47                         else if (PageSlab(page))
  48                                 slab++;
  49                         else if (!page_count(page))
  50                                 free++;
  51                         else
  52                                 shared += page_count(page) - 1;
  53                 }
  54                 pgdat_resize_unlock(pgdat, &flags);
  55         }
  56
  57         printk("Free swap:       %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
  58         printk("%d pages of RAM\n", total);
  59         printk("%d free pages\n", free);
  60         printk("%d reserved pages\n", reserved);
  61         printk("%d slab pages\n", slab);
  62         printk("%d pages shared\n", shared);
  63         printk("%d pages swap cached\n", cached);
  64         printk(KERN_INFO "Total of %ld pages in page table cache\n",
  65                quicklist_total_size());
  66 }
  67
  68 #ifdef CONFIG_MMU
  69 static void set_pte_phys(unsigned long addr, unsigned long phys, pgprot_t prot)
  70 {
  71         pgd_t *pgd;
  72         pud_t *pud;
  73         pmd_t *pmd;
  74         pte_t *pte;
  75
  76         pgd = pgd_offset_k(addr);
  77         if (pgd_none(*pgd)) {
  78                 pgd_ERROR(*pgd);
  79                 return;
  80         }
  81
  82         pud = pud_alloc(NULL, pgd, addr);
  83         if (unlikely(!pud)) {
  84                 pud_ERROR(*pud);
  85                 return;
  86         }
  87
  88         pmd = pmd_alloc(NULL, pud, addr);
  89         if (unlikely(!pmd)) {
  90                 pmd_ERROR(*pmd);
  91                 return;
  92         }
  93
  94         pte = pte_offset_kernel(pmd, addr);
  95         if (!pte_none(*pte)) {
  96                 pte_ERROR(*pte);
  97                 return;
  98         }
  99
 100         set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, prot));
 101
 102         flush_tlb_one(get_asid(), addr);
 103 }
 104
 105 /*
 106  * As a performance optimization, other platforms preserve the fixmap mapping
 107  * across a context switch, we don't presently do this, but this could be done
 108  * in a similar fashion as to the wired TLB interface that sh64 uses (by way
 109  * of the memory mapped UTLB configuration) -- this unfortunately forces us to
 110  * give up a TLB entry for each mapping we want to preserve. While this may be
 111  * viable for a small number of fixmaps, it's not particularly useful for
 112  * everything and needs to be carefully evaluated. (ie, we may want this for
 113  * the vsyscall page).
 114  *
 115  * XXX: Perhaps add a _PAGE_WIRED flag or something similar that we can pass
 116  * in at __set_fixmap() time to determine the appropriate behavior to follow.
 117  *
 118  *                                       -- PFM.
 119  */
 120 void __set_fixmap(enum fixed_addresses idx, unsigned long phys, pgprot_t prot)
 121 {
 122         unsigned long address = __fix_to_virt(idx);
 123
 124         if (idx >= __end_of_fixed_addresses) {
 125                 BUG();
 126                 return;
 127         }
 128
 129         set_pte_phys(address, phys, prot);
 130 }
 131 #endif  /* CONFIG_MMU */
 132
 133 /*
 134  * paging_init() sets up the page tables
 135  */
 136 void __init paging_init(void)
 137 {
 138         unsigned long max_zone_pfns[MAX_NR_ZONES];
 139         int nid;
 140
 141         /* We don't need to map the kernel through the TLB, as
 142          * it is permanatly mapped using P1. So clear the
 143          * entire pgd. */
 144         memset(swapper_pg_dir, 0, sizeof(swapper_pg_dir));
 145
 146         /* Set an initial value for the MMU.TTB so we don't have to
 147          * check for a null value. */
 148         set_TTB(swapper_pg_dir);
 149
 150         memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
 151
 152         for_each_online_node(nid) {
 153                 pg_data_t *pgdat = NODE_DATA(nid);
 154                 unsigned long low, start_pfn;
 155
 156                 start_pfn = pgdat->bdata->node_boot_start >> PAGE_SHIFT;
 157                 low = pgdat->bdata->node_low_pfn;
 158
 159                 if (max_zone_pfns[ZONE_NORMAL] < low)
 160                         max_zone_pfns[ZONE_NORMAL] = low;
 161
 162                 printk("Node %u: start_pfn = 0x%lx, low = 0x%lx\n",
 163                        nid, start_pfn, low);
 164         }
 165
 166         free_area_init_nodes(max_zone_pfns);
 167 }
 168
 169 static struct kcore_list kcore_mem, kcore_vmalloc;
 170 int after_bootmem = 0;
 171
 172 void __init mem_init(void)
 173 {
 174         int codesize, datasize, initsize;
 175         int nid;
 176
 177         num_physpages = 0;
 178         high_memory = NULL;
 179
 180         for_each_online_node(nid) {
 181                 pg_data_t *pgdat = NODE_DATA(nid);
 182                 unsigned long node_pages = 0;
 183                 void *node_high_memory;
 184
 185                 num_physpages += pgdat->node_present_pages;
 186
 187                 if (pgdat->node_spanned_pages)
 188                         node_pages = free_all_bootmem_node(pgdat);
 189
 190                 totalram_pages += node_pages;
 191
 192                 node_high_memory = (void *)__va((pgdat->node_start_pfn +
 193                                                  pgdat->node_spanned_pages) <<
 194                                                  PAGE_SHIFT);
 195                 if (node_high_memory > high_memory)
 196                         high_memory = node_high_memory;
 197         }
 198
 199         /* clear the zero-page */
 200         memset(empty_zero_page, 0, PAGE_SIZE);
 201         __flush_wback_region(empty_zero_page, PAGE_SIZE);
 202
 203         after_bootmem = 1;
 204
 205         codesize =  (unsigned long) &_etext - (unsigned long) &_text;
 206         datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
 207         initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
 208
 209         kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
 210         kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
 211                    VMALLOC_END - VMALLOC_START);
 212
 213         printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, "
 214                "%dk data, %dk init)\n",
 215                 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
 216                 num_physpages << (PAGE_SHIFT-10),
 217                 codesize >> 10,
 218                 datasize >> 10,
 219                 initsize >> 10);
 220
 221         p3_cache_init();
 222
 223         /* Initialize the vDSO */
 224         vsyscall_init();
 225 }
 226
 227 void free_initmem(void)
 228 {
 229         unsigned long addr;
 230
 231         addr = (unsigned long)(&__init_begin);
 232         for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
 233                 ClearPageReserved(virt_to_page(addr));
 234                 init_page_count(virt_to_page(addr));
 235                 free_page(addr);
 236                 totalram_pages++;
 237         }
 238         printk("Freeing unused kernel memory: %ldk freed\n",
 239                ((unsigned long)&__init_end -
 240                 (unsigned long)&__init_begin) >> 10);
 241 }
 242
 243 #ifdef CONFIG_BLK_DEV_INITRD
 244 void free_initrd_mem(unsigned long start, unsigned long end)
 245 {
 246         unsigned long p;
 247         for (p = start; p < end; p += PAGE_SIZE) {
 248                 ClearPageReserved(virt_to_page(p));
 249                 init_page_count(virt_to_page(p));
 250                 free_page(p);
 251                 totalram_pages++;
 252         }
 253         printk("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
 254 }
 255 #endif
 256
 257 #ifdef CONFIG_MEMORY_HOTPLUG
 258 void online_page(struct page *page)
 259 {
 260         ClearPageReserved(page);
 261         init_page_count(page);
 262         __free_page(page);
 263         totalram_pages++;
 264         num_physpages++;
 265 }
 266
 267 int arch_add_memory(int nid, u64 start, u64 size)
 268 {
 269         pg_data_t *pgdat;
 270         unsigned long start_pfn = start >> PAGE_SHIFT;
 271         unsigned long nr_pages = size >> PAGE_SHIFT;
 272         int ret;
 273
 274         pgdat = NODE_DATA(nid);
 275
 276         /* We only have ZONE_NORMAL, so this is easy.. */
 277         ret = __add_pages(pgdat->node_zones + ZONE_NORMAL, start_pfn, nr_pages);
 278         if (unlikely(ret))
 279                 printk("%s: Failed, __add_pages() == %d\n", __FUNCTION__, ret);
 280
 281         return ret;
 282 }
 283 EXPORT_SYMBOL_GPL(arch_add_memory);
 284
 285 #ifdef CONFIG_NUMA
 286 int memory_add_physaddr_to_nid(u64 addr)
 287 {
 288         /* Node 0 for now.. */
 289         return 0;
 290 }
 291 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
 292 #endif
 293 #endif