/* * arch/s390/mm/init.c * * S390 version * Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation * Author(s): Hartmut Penner (hp@de.ibm.com) * * Derived from "arch/i386/mm/init.c" * Copyright (C) 1995 Linus Torvalds */ #include <linux/config.h> #include <linux/signal.h> #include <linux/sched.h> #include <linux/kernel.h> #include <linux/errno.h> #include <linux/string.h> #include <linux/types.h> #include <linux/ptrace.h> #include <linux/mman.h> #include <linux/mm.h> #include <linux/swap.h> #include <linux/smp.h> #include <linux/init.h> #ifdef CONFIG_BLK_DEV_INITRD #include <linux/blk.h> #endif #include <linux/pagemap.h> #include <linux/bootmem.h> #include <asm/processor.h> #include <asm/system.h> #include <asm/uaccess.h> #include <asm/pgtable.h> #include <asm/pgalloc.h> #include <asm/dma.h> #include <asm/lowcore.h> #include <asm/tlb.h> #include <asm/tlbflush.h> mmu_gather_t mmu_gathers[NR_CPUS]; pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__((__aligned__(PAGE_SIZE))); char empty_zero_page[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE))); void show_mem(void) { int i, total = 0, reserved = 0; int shared = 0, cached = 0; printk("Mem-info:\n"); show_free_areas(); printk("Free swap: %6dkB\n",nr_swap_pages<<(PAGE_SHIFT-10)); i = max_mapnr; while (i-- > 0) { total++; if (PageReserved(mem_map+i)) reserved++; else if (PageSwapCache(mem_map+i)) cached++; else if (page_count(mem_map+i)) shared += atomic_read(&mem_map[i].count) - 1; } printk("%d pages of RAM\n",total); printk("%d reserved pages\n",reserved); printk("%d pages shared\n",shared); printk("%d pages swap cached\n",cached); } /* References to section boundaries */ extern unsigned long _text; extern unsigned long _etext; extern unsigned long _edata; extern unsigned long __bss_start; extern unsigned long _end; extern unsigned long __init_begin; extern unsigned long __init_end; /* * paging_init() sets up the page tables - note that the first 4MB are * already mapped by head.S. * paging_init will erase this initial mapping */ unsigned long last_valid_pfn; void __init paging_init(void) { pgd_t * pg_dir; pte_t * pg_table; pte_t pte; int i; unsigned long tmp; unsigned long pfn = 0; unsigned long pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | _KERNSEG_TABLE; static const int ssm_mask = 0x04000000L; /* unmap whole virtual address space */ pg_dir = swapper_pg_dir; for (i=0;i<KERNEL_PGD_PTRS;i++) pmd_clear((pmd_t*)pg_dir++); /* * map whole physical memory to virtual memory (identity mapping) */ pg_dir = swapper_pg_dir; while (pfn < max_low_pfn) { /* * pg_table is physical at this point */ pg_table = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE); pg_dir->pgd0 = (_PAGE_TABLE | __pa(pg_table)); pg_dir->pgd1 = (_PAGE_TABLE | (__pa(pg_table)+1024)); pg_dir->pgd2 = (_PAGE_TABLE | (__pa(pg_table)+2048)); pg_dir->pgd3 = (_PAGE_TABLE | (__pa(pg_table)+3072)); pg_dir++; for (tmp = 0 ; tmp < PTRS_PER_PTE ; tmp++,pg_table++) { pte = pfn_pte(pfn, PAGE_KERNEL); if (pfn >= max_low_pfn) pte_clear(&pte); set_pte(pg_table, pte); pfn++; } } /* enable virtual mapping in kernel mode */ __asm__ __volatile__(" LCTL 1,1,%0\n" " LCTL 7,7,%0\n" " LCTL 13,13,%0\n" " SSM %1" : : "m" (pgdir_k), "m" (ssm_mask)); local_flush_tlb(); { unsigned long zones_size[MAX_NR_ZONES] = { 0, 0, 0}; zones_size[ZONE_DMA] = max_low_pfn; free_area_init(zones_size); } return; } void __init mem_init(void) { int codesize, reservedpages, datasize, initsize; max_mapnr = num_physpages = max_low_pfn; high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); /* clear the zero-page */ memset(empty_zero_page, 0, PAGE_SIZE); /* this will put all low memory onto the freelists */ totalram_pages += free_all_bootmem(); reservedpages = 0; codesize = (unsigned long) &_etext - (unsigned long) &_text; datasize = (unsigned long) &_edata - (unsigned long) &_etext; initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin; printk("Memory: %luk/%luk available (%dk kernel code, %dk reserved, %dk data, %dk init)\n", (unsigned long) nr_free_pages() << (PAGE_SHIFT-10), max_mapnr << (PAGE_SHIFT-10), codesize >> 10, reservedpages << (PAGE_SHIFT-10), datasize >>10, initsize >> 10); } void free_initmem(void) { unsigned long addr; addr = (unsigned long)(&__init_begin); for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) { ClearPageReserved(virt_to_page(addr)); set_page_count(virt_to_page(addr), 1); free_page(addr); totalram_pages++; } printk ("Freeing unused kernel memory: %dk freed\n", (&__init_end - &__init_begin) >> 10); } #ifdef CONFIG_BLK_DEV_INITRD void free_initrd_mem(unsigned long start, unsigned long end) { if (start < end) printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10); for (; start < end; start += PAGE_SIZE) { ClearPageReserved(virt_to_page(start)); set_page_count(virt_to_page(start), 1); free_page(start); totalram_pages++; } } #endif