202 lines
		
	
	
		
			5.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			202 lines
		
	
	
		
			5.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  *  linux/arch/h8300/mm/init.c
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|  *
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|  *  Copyright (C) 1998  D. Jeff Dionne <jeff@lineo.ca>,
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|  *                      Kenneth Albanowski <kjahds@kjahds.com>,
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|  *  Copyright (C) 2000  Lineo, Inc.  (www.lineo.com) 
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|  *
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|  *  Based on:
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|  *
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|  *  linux/arch/m68knommu/mm/init.c
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|  *  linux/arch/m68k/mm/init.c
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|  *
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|  *  Copyright (C) 1995  Hamish Macdonald
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|  *
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|  *  JAN/1999 -- hacked to support ColdFire (gerg@snapgear.com)
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|  *  DEC/2000 -- linux 2.4 support <davidm@snapgear.com>
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|  */
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| 
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| #include <linux/signal.h>
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| #include <linux/sched.h>
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| #include <linux/kernel.h>
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| #include <linux/errno.h>
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| #include <linux/string.h>
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| #include <linux/types.h>
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| #include <linux/ptrace.h>
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| #include <linux/mman.h>
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| #include <linux/mm.h>
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| #include <linux/swap.h>
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| #include <linux/init.h>
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| #include <linux/highmem.h>
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| #include <linux/pagemap.h>
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| #include <linux/bootmem.h>
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| #include <linux/slab.h>
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| 
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| #include <asm/setup.h>
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| #include <asm/segment.h>
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| #include <asm/page.h>
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| #include <asm/pgtable.h>
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| #include <asm/system.h>
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| 
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| #undef DEBUG
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| 
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| /*
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|  * BAD_PAGE is the page that is used for page faults when linux
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|  * is out-of-memory. Older versions of linux just did a
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|  * do_exit(), but using this instead means there is less risk
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|  * for a process dying in kernel mode, possibly leaving a inode
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|  * unused etc..
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|  *
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|  * BAD_PAGETABLE is the accompanying page-table: it is initialized
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|  * to point to BAD_PAGE entries.
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|  *
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|  * ZERO_PAGE is a special page that is used for zero-initialized
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|  * data and COW.
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|  */
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| static unsigned long empty_bad_page_table;
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| 
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| static unsigned long empty_bad_page;
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| 
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| unsigned long empty_zero_page;
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| 
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| extern unsigned long rom_length;
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| 
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| extern unsigned long memory_start;
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| extern unsigned long memory_end;
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| 
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| /*
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|  * paging_init() continues the virtual memory environment setup which
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|  * was begun by the code in arch/head.S.
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|  * The parameters are pointers to where to stick the starting and ending
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|  * addresses of available kernel virtual memory.
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|  */
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| void __init paging_init(void)
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| {
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| 	/*
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| 	 * Make sure start_mem is page aligned,  otherwise bootmem and
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| 	 * page_alloc get different views og the world.
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| 	 */
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| #ifdef DEBUG
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| 	unsigned long start_mem = PAGE_ALIGN(memory_start);
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| #endif
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| 	unsigned long end_mem   = memory_end & PAGE_MASK;
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| 
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| #ifdef DEBUG
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| 	printk ("start_mem is %#lx\nvirtual_end is %#lx\n",
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| 		start_mem, end_mem);
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| #endif
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| 
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| 	/*
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| 	 * Initialize the bad page table and bad page to point
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| 	 * to a couple of allocated pages.
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| 	 */
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| 	empty_bad_page_table = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
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| 	empty_bad_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
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| 	empty_zero_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
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| 	memset((void *)empty_zero_page, 0, PAGE_SIZE);
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| 
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| 	/*
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| 	 * Set up SFC/DFC registers (user data space).
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| 	 */
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| 	set_fs (USER_DS);
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| 
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| #ifdef DEBUG
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| 	printk ("before free_area_init\n");
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| 
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| 	printk ("free_area_init -> start_mem is %#lx\nvirtual_end is %#lx\n",
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| 		start_mem, end_mem);
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| #endif
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| 
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| 	{
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| 		unsigned long zones_size[MAX_NR_ZONES] = {0, };
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| 
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| 		zones_size[ZONE_DMA]     = 0 >> PAGE_SHIFT;
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| 		zones_size[ZONE_NORMAL]  = (end_mem - PAGE_OFFSET) >> PAGE_SHIFT;
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| #ifdef CONFIG_HIGHMEM
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| 		zones_size[ZONE_HIGHMEM] = 0;
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| #endif
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| 		free_area_init(zones_size);
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| 	}
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| }
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| 
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| void __init mem_init(void)
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| {
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| 	int codek = 0, datak = 0, initk = 0;
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| 	/* DAVIDM look at setup memory map generically with reserved area */
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| 	unsigned long tmp;
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| 	extern char _etext, _stext, _sdata, _ebss, __init_begin, __init_end;
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| 	extern unsigned long  _ramend, _ramstart;
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| 	unsigned long len = &_ramend - &_ramstart;
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| 	unsigned long start_mem = memory_start; /* DAVIDM - these must start at end of kernel */
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| 	unsigned long end_mem   = memory_end; /* DAVIDM - this must not include kernel stack at top */
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| 
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| #ifdef DEBUG
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| 	printk(KERN_DEBUG "Mem_init: start=%lx, end=%lx\n", start_mem, end_mem);
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| #endif
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| 
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| 	end_mem &= PAGE_MASK;
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| 	high_memory = (void *) end_mem;
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| 
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| 	start_mem = PAGE_ALIGN(start_mem);
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| 	max_mapnr = num_physpages = MAP_NR(high_memory);
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| 
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| 	/* this will put all memory onto the freelists */
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| 	totalram_pages = free_all_bootmem();
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| 
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| 	codek = (&_etext - &_stext) >> 10;
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| 	datak = (&_ebss - &_sdata) >> 10;
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| 	initk = (&__init_begin - &__init_end) >> 10;
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| 
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| 	tmp = nr_free_pages() << PAGE_SHIFT;
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| 	printk(KERN_INFO "Memory available: %luk/%luk RAM, %luk/%luk ROM (%dk kernel code, %dk data)\n",
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| 	       tmp >> 10,
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| 	       len >> 10,
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| 	       (rom_length > 0) ? ((rom_length >> 10) - codek) : 0,
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| 	       rom_length >> 10,
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| 	       codek,
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| 	       datak
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| 	       );
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| }
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| 
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| 
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| #ifdef CONFIG_BLK_DEV_INITRD
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| void free_initrd_mem(unsigned long start, unsigned long end)
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| {
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| 	int pages = 0;
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| 	for (; start < end; start += PAGE_SIZE) {
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| 		ClearPageReserved(virt_to_page(start));
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| 		init_page_count(virt_to_page(start));
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| 		free_page(start);
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| 		totalram_pages++;
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| 		pages++;
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| 	}
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| 	printk ("Freeing initrd memory: %dk freed\n", pages);
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| }
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| #endif
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| 
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| void
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| free_initmem(void)
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| {
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| #ifdef CONFIG_RAMKERNEL
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| 	unsigned long addr;
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| 	extern char __init_begin, __init_end;
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| /*
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|  *	the following code should be cool even if these sections
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|  *	are not page aligned.
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|  */
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| 	addr = PAGE_ALIGN((unsigned long)(&__init_begin));
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| 	/* next to check that the page we free is not a partial page */
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| 	for (; addr + PAGE_SIZE < (unsigned long)(&__init_end); addr +=PAGE_SIZE) {
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| 		ClearPageReserved(virt_to_page(addr));
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| 		init_page_count(virt_to_page(addr));
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| 		free_page(addr);
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| 		totalram_pages++;
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| 	}
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| 	printk(KERN_INFO "Freeing unused kernel memory: %ldk freed (0x%x - 0x%x)\n",
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| 			(addr - PAGE_ALIGN((long) &__init_begin)) >> 10,
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| 			(int)(PAGE_ALIGN((unsigned long)(&__init_begin))),
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| 			(int)(addr - PAGE_SIZE));
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| #endif
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| }
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| 
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