|  | /* | 
|  | *  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> | 
|  | #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> | 
|  |  | 
|  | DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); | 
|  |  | 
|  | pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__((__aligned__(PAGE_SIZE))); | 
|  | char  empty_zero_page[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE))); | 
|  |  | 
|  | void diag10(unsigned long addr) | 
|  | { | 
|  | if (addr >= 0x7ff00000) | 
|  | return; | 
|  | #ifdef __s390x__ | 
|  | asm volatile ( | 
|  | "   sam31\n" | 
|  | "   diag %0,%0,0x10\n" | 
|  | "0: sam64\n" | 
|  | ".section __ex_table,\"a\"\n" | 
|  | "   .align 8\n" | 
|  | "   .quad 0b, 0b\n" | 
|  | ".previous\n" | 
|  | : : "a" (addr)); | 
|  | #else | 
|  | asm volatile ( | 
|  | "   diag %0,%0,0x10\n" | 
|  | "0:\n" | 
|  | ".section __ex_table,\"a\"\n" | 
|  | "   .align 4\n" | 
|  | "   .long 0b, 0b\n" | 
|  | ".previous\n" | 
|  | : : "a" (addr)); | 
|  | #endif | 
|  | } | 
|  |  | 
|  | 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:       %6ldkB\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 += page_count(mem_map+i) - 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; | 
|  |  | 
|  | extern unsigned long __initdata zholes_size[]; | 
|  | /* | 
|  | * paging_init() sets up the page tables | 
|  | */ | 
|  |  | 
|  | #ifndef CONFIG_ARCH_S390X | 
|  | 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(&init_mm, 0, &pte); | 
|  | set_pte(pg_table, pte); | 
|  | pfn++; | 
|  | } | 
|  | } | 
|  |  | 
|  | S390_lowcore.kernel_asce = pgdir_k; | 
|  |  | 
|  | /* 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]; | 
|  |  | 
|  | memset(zones_size, 0, sizeof(zones_size)); | 
|  | zones_size[ZONE_DMA] = max_low_pfn; | 
|  | free_area_init_node(0, &contig_page_data, zones_size, | 
|  | __pa(PAGE_OFFSET) >> PAGE_SHIFT, | 
|  | zholes_size); | 
|  | } | 
|  | return; | 
|  | } | 
|  |  | 
|  | #else /* CONFIG_ARCH_S390X */ | 
|  | void __init paging_init(void) | 
|  | { | 
|  | pgd_t * pg_dir; | 
|  | pmd_t * pm_dir; | 
|  | pte_t * pt_dir; | 
|  | pte_t   pte; | 
|  | int     i,j,k; | 
|  | unsigned long pfn = 0; | 
|  | unsigned long pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | | 
|  | _KERN_REGION_TABLE; | 
|  | static const int ssm_mask = 0x04000000L; | 
|  |  | 
|  | unsigned long zones_size[MAX_NR_ZONES]; | 
|  | unsigned long dma_pfn, high_pfn; | 
|  |  | 
|  | memset(zones_size, 0, sizeof(zones_size)); | 
|  | dma_pfn = MAX_DMA_ADDRESS >> PAGE_SHIFT; | 
|  | high_pfn = max_low_pfn; | 
|  |  | 
|  | if (dma_pfn > high_pfn) | 
|  | zones_size[ZONE_DMA] = high_pfn; | 
|  | else { | 
|  | zones_size[ZONE_DMA] = dma_pfn; | 
|  | zones_size[ZONE_NORMAL] = high_pfn - dma_pfn; | 
|  | } | 
|  |  | 
|  | /* Initialize mem_map[].  */ | 
|  | free_area_init_node(0, &contig_page_data, zones_size, | 
|  | __pa(PAGE_OFFSET) >> PAGE_SHIFT, zholes_size); | 
|  |  | 
|  | /* | 
|  | * map whole physical memory to virtual memory (identity mapping) | 
|  | */ | 
|  |  | 
|  | pg_dir = swapper_pg_dir; | 
|  |  | 
|  | for (i = 0 ; i < PTRS_PER_PGD ; i++,pg_dir++) { | 
|  |  | 
|  | if (pfn >= max_low_pfn) { | 
|  | pgd_clear(pg_dir); | 
|  | continue; | 
|  | } | 
|  |  | 
|  | pm_dir = (pmd_t *) alloc_bootmem_low_pages(PAGE_SIZE*4); | 
|  | pgd_populate(&init_mm, pg_dir, pm_dir); | 
|  |  | 
|  | for (j = 0 ; j < PTRS_PER_PMD ; j++,pm_dir++) { | 
|  | if (pfn >= max_low_pfn) { | 
|  | pmd_clear(pm_dir); | 
|  | continue; | 
|  | } | 
|  |  | 
|  | pt_dir = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE); | 
|  | pmd_populate_kernel(&init_mm, pm_dir, pt_dir); | 
|  |  | 
|  | for (k = 0 ; k < PTRS_PER_PTE ; k++,pt_dir++) { | 
|  | pte = pfn_pte(pfn, PAGE_KERNEL); | 
|  | if (pfn >= max_low_pfn) { | 
|  | pte_clear(&init_mm, 0, &pte); | 
|  | continue; | 
|  | } | 
|  | set_pte(pt_dir, pte); | 
|  | pfn++; | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | S390_lowcore.kernel_asce = pgdir_k; | 
|  |  | 
|  | /* enable virtual mapping in kernel mode */ | 
|  | __asm__ __volatile__("lctlg 1,1,%0\n\t" | 
|  | "lctlg 7,7,%0\n\t" | 
|  | "lctlg 13,13,%0\n\t" | 
|  | "ssm   %1" | 
|  | : :"m" (pgdir_k), "m" (ssm_mask)); | 
|  |  | 
|  | local_flush_tlb(); | 
|  |  | 
|  | return; | 
|  | } | 
|  | #endif /* CONFIG_ARCH_S390X */ | 
|  |  | 
|  | void __init mem_init(void) | 
|  | { | 
|  | unsigned long 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 (%ldk kernel code, %ldk reserved, %ldk data, %ldk 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: %ldk freed\n", | 
|  | ((unsigned long)&__init_end - (unsigned long)&__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 |