| /* | 
 |  *  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 |