608 lines
16 KiB
C
608 lines
16 KiB
C
/*
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* PowerPC version
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* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
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*
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* Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
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* and Cort Dougan (PReP) (cort@cs.nmt.edu)
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* Copyright (C) 1996 Paul Mackerras
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* PPC44x/36-bit changes by Matt Porter (mporter@mvista.com)
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*
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* Derived from "arch/i386/mm/init.c"
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* Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*
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*/
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#include <linux/export.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/gfp.h>
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#include <linux/types.h>
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#include <linux/mm.h>
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#include <linux/stddef.h>
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#include <linux/init.h>
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#include <linux/bootmem.h>
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#include <linux/highmem.h>
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#include <linux/initrd.h>
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#include <linux/pagemap.h>
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#include <linux/suspend.h>
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#include <linux/memblock.h>
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#include <linux/hugetlb.h>
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#include <linux/slab.h>
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#include <asm/pgalloc.h>
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#include <asm/prom.h>
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#include <asm/io.h>
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#include <asm/mmu_context.h>
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#include <asm/pgtable.h>
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#include <asm/mmu.h>
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#include <asm/smp.h>
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#include <asm/machdep.h>
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#include <asm/btext.h>
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#include <asm/tlb.h>
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#include <asm/sections.h>
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#include <asm/sparsemem.h>
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#include <asm/vdso.h>
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#include <asm/fixmap.h>
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#include <asm/swiotlb.h>
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#include <asm/rtas.h>
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#include "mmu_decl.h"
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#ifndef CPU_FTR_COHERENT_ICACHE
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#define CPU_FTR_COHERENT_ICACHE 0 /* XXX for now */
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#define CPU_FTR_NOEXECUTE 0
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#endif
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int init_bootmem_done;
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int mem_init_done;
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phys_addr_t memory_limit;
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#ifdef CONFIG_HIGHMEM
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pte_t *kmap_pte;
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pgprot_t kmap_prot;
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EXPORT_SYMBOL(kmap_prot);
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EXPORT_SYMBOL(kmap_pte);
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static inline pte_t *virt_to_kpte(unsigned long vaddr)
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{
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return pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr),
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vaddr), vaddr), vaddr);
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}
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#endif
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int page_is_ram(unsigned long pfn)
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{
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#ifndef CONFIG_PPC64 /* XXX for now */
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return pfn < max_pfn;
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#else
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unsigned long paddr = (pfn << PAGE_SHIFT);
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struct memblock_region *reg;
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for_each_memblock(memory, reg)
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if (paddr >= reg->base && paddr < (reg->base + reg->size))
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return 1;
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return 0;
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#endif
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}
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pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
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unsigned long size, pgprot_t vma_prot)
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{
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if (ppc_md.phys_mem_access_prot)
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return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot);
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if (!page_is_ram(pfn))
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vma_prot = pgprot_noncached(vma_prot);
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return vma_prot;
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}
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EXPORT_SYMBOL(phys_mem_access_prot);
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#ifdef CONFIG_MEMORY_HOTPLUG
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#ifdef CONFIG_NUMA
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int memory_add_physaddr_to_nid(u64 start)
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{
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return hot_add_scn_to_nid(start);
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}
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#endif
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int arch_add_memory(int nid, u64 start, u64 size)
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{
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struct pglist_data *pgdata;
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struct zone *zone;
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unsigned long start_pfn = start >> PAGE_SHIFT;
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unsigned long nr_pages = size >> PAGE_SHIFT;
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pgdata = NODE_DATA(nid);
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start = (unsigned long)__va(start);
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if (create_section_mapping(start, start + size))
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return -EINVAL;
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/* this should work for most non-highmem platforms */
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zone = pgdata->node_zones;
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return __add_pages(nid, zone, start_pfn, nr_pages);
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}
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#endif /* CONFIG_MEMORY_HOTPLUG */
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/*
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* walk_memory_resource() needs to make sure there is no holes in a given
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* memory range. PPC64 does not maintain the memory layout in /proc/iomem.
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* Instead it maintains it in memblock.memory structures. Walk through the
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* memory regions, find holes and callback for contiguous regions.
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*/
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int
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walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages,
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void *arg, int (*func)(unsigned long, unsigned long, void *))
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{
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struct memblock_region *reg;
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unsigned long end_pfn = start_pfn + nr_pages;
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unsigned long tstart, tend;
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int ret = -1;
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for_each_memblock(memory, reg) {
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tstart = max(start_pfn, memblock_region_memory_base_pfn(reg));
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tend = min(end_pfn, memblock_region_memory_end_pfn(reg));
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if (tstart >= tend)
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continue;
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ret = (*func)(tstart, tend - tstart, arg);
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if (ret)
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break;
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}
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return ret;
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}
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EXPORT_SYMBOL_GPL(walk_system_ram_range);
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/*
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* Initialize the bootmem system and give it all the memory we
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* have available. If we are using highmem, we only put the
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* lowmem into the bootmem system.
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*/
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#ifndef CONFIG_NEED_MULTIPLE_NODES
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void __init do_init_bootmem(void)
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{
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unsigned long start, bootmap_pages;
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unsigned long total_pages;
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struct memblock_region *reg;
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int boot_mapsize;
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max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
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total_pages = (memblock_end_of_DRAM() - memstart_addr) >> PAGE_SHIFT;
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#ifdef CONFIG_HIGHMEM
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total_pages = total_lowmem >> PAGE_SHIFT;
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max_low_pfn = lowmem_end_addr >> PAGE_SHIFT;
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#endif
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/*
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* Find an area to use for the bootmem bitmap. Calculate the size of
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* bitmap required as (Total Memory) / PAGE_SIZE / BITS_PER_BYTE.
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* Add 1 additional page in case the address isn't page-aligned.
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*/
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bootmap_pages = bootmem_bootmap_pages(total_pages);
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start = memblock_alloc(bootmap_pages << PAGE_SHIFT, PAGE_SIZE);
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min_low_pfn = MEMORY_START >> PAGE_SHIFT;
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boot_mapsize = init_bootmem_node(NODE_DATA(0), start >> PAGE_SHIFT, min_low_pfn, max_low_pfn);
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/* Add active regions with valid PFNs */
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for_each_memblock(memory, reg) {
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unsigned long start_pfn, end_pfn;
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start_pfn = memblock_region_memory_base_pfn(reg);
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end_pfn = memblock_region_memory_end_pfn(reg);
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memblock_set_node(0, (phys_addr_t)ULLONG_MAX, 0);
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}
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/* Add all physical memory to the bootmem map, mark each area
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* present.
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*/
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#ifdef CONFIG_HIGHMEM
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free_bootmem_with_active_regions(0, lowmem_end_addr >> PAGE_SHIFT);
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/* reserve the sections we're already using */
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for_each_memblock(reserved, reg) {
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unsigned long top = reg->base + reg->size - 1;
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if (top < lowmem_end_addr)
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reserve_bootmem(reg->base, reg->size, BOOTMEM_DEFAULT);
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else if (reg->base < lowmem_end_addr) {
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unsigned long trunc_size = lowmem_end_addr - reg->base;
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reserve_bootmem(reg->base, trunc_size, BOOTMEM_DEFAULT);
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}
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}
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#else
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free_bootmem_with_active_regions(0, max_pfn);
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/* reserve the sections we're already using */
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for_each_memblock(reserved, reg)
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reserve_bootmem(reg->base, reg->size, BOOTMEM_DEFAULT);
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#endif
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/* XXX need to clip this if using highmem? */
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sparse_memory_present_with_active_regions(0);
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init_bootmem_done = 1;
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}
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/* mark pages that don't exist as nosave */
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static int __init mark_nonram_nosave(void)
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{
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struct memblock_region *reg, *prev = NULL;
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for_each_memblock(memory, reg) {
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if (prev &&
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memblock_region_memory_end_pfn(prev) < memblock_region_memory_base_pfn(reg))
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register_nosave_region(memblock_region_memory_end_pfn(prev),
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memblock_region_memory_base_pfn(reg));
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prev = reg;
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}
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return 0;
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}
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/*
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* paging_init() sets up the page tables - in fact we've already done this.
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*/
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void __init paging_init(void)
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{
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unsigned long long total_ram = memblock_phys_mem_size();
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phys_addr_t top_of_ram = memblock_end_of_DRAM();
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unsigned long max_zone_pfns[MAX_NR_ZONES];
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#ifdef CONFIG_PPC32
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unsigned long v = __fix_to_virt(__end_of_fixed_addresses - 1);
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unsigned long end = __fix_to_virt(FIX_HOLE);
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for (; v < end; v += PAGE_SIZE)
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map_page(v, 0, 0); /* XXX gross */
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#endif
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#ifdef CONFIG_HIGHMEM
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map_page(PKMAP_BASE, 0, 0); /* XXX gross */
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pkmap_page_table = virt_to_kpte(PKMAP_BASE);
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kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
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kmap_prot = PAGE_KERNEL;
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#endif /* CONFIG_HIGHMEM */
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printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n",
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(unsigned long long)top_of_ram, total_ram);
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printk(KERN_DEBUG "Memory hole size: %ldMB\n",
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(long int)((top_of_ram - total_ram) >> 20));
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memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
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#ifdef CONFIG_HIGHMEM
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max_zone_pfns[ZONE_DMA] = lowmem_end_addr >> PAGE_SHIFT;
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max_zone_pfns[ZONE_HIGHMEM] = top_of_ram >> PAGE_SHIFT;
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#else
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max_zone_pfns[ZONE_DMA] = top_of_ram >> PAGE_SHIFT;
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#endif
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free_area_init_nodes(max_zone_pfns);
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mark_nonram_nosave();
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}
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#endif /* ! CONFIG_NEED_MULTIPLE_NODES */
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void __init mem_init(void)
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{
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#ifdef CONFIG_NEED_MULTIPLE_NODES
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int nid;
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#endif
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pg_data_t *pgdat;
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unsigned long i;
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struct page *page;
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unsigned long reservedpages = 0, codesize, initsize, datasize, bsssize;
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#ifdef CONFIG_SWIOTLB
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if (ppc_swiotlb_enable)
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swiotlb_init(1);
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#endif
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num_physpages = memblock_phys_mem_size() >> PAGE_SHIFT;
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high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
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#ifdef CONFIG_NEED_MULTIPLE_NODES
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for_each_online_node(nid) {
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if (NODE_DATA(nid)->node_spanned_pages != 0) {
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printk("freeing bootmem node %d\n", nid);
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totalram_pages +=
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free_all_bootmem_node(NODE_DATA(nid));
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}
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}
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#else
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max_mapnr = max_pfn;
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totalram_pages += free_all_bootmem();
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#endif
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for_each_online_pgdat(pgdat) {
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for (i = 0; i < pgdat->node_spanned_pages; i++) {
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if (!pfn_valid(pgdat->node_start_pfn + i))
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continue;
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page = pgdat_page_nr(pgdat, i);
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if (PageReserved(page))
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reservedpages++;
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}
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}
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codesize = (unsigned long)&_sdata - (unsigned long)&_stext;
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datasize = (unsigned long)&_edata - (unsigned long)&_sdata;
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initsize = (unsigned long)&__init_end - (unsigned long)&__init_begin;
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bsssize = (unsigned long)&__bss_stop - (unsigned long)&__bss_start;
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#ifdef CONFIG_HIGHMEM
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{
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unsigned long pfn, highmem_mapnr;
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highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT;
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for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) {
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phys_addr_t paddr = (phys_addr_t)pfn << PAGE_SHIFT;
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struct page *page = pfn_to_page(pfn);
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if (memblock_is_reserved(paddr))
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continue;
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ClearPageReserved(page);
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init_page_count(page);
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__free_page(page);
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totalhigh_pages++;
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reservedpages--;
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}
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totalram_pages += totalhigh_pages;
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printk(KERN_DEBUG "High memory: %luk\n",
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totalhigh_pages << (PAGE_SHIFT-10));
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}
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#endif /* CONFIG_HIGHMEM */
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#if defined(CONFIG_PPC_FSL_BOOK3E) && !defined(CONFIG_SMP)
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/*
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* If smp is enabled, next_tlbcam_idx is initialized in the cpu up
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* functions.... do it here for the non-smp case.
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*/
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per_cpu(next_tlbcam_idx, smp_processor_id()) =
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(mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1;
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#endif
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printk(KERN_INFO "Memory: %luk/%luk available (%luk kernel code, "
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"%luk reserved, %luk data, %luk bss, %luk init)\n",
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nr_free_pages() << (PAGE_SHIFT-10),
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num_physpages << (PAGE_SHIFT-10),
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codesize >> 10,
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reservedpages << (PAGE_SHIFT-10),
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datasize >> 10,
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bsssize >> 10,
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initsize >> 10);
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#ifdef CONFIG_PPC32
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pr_info("Kernel virtual memory layout:\n");
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pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP);
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#ifdef CONFIG_HIGHMEM
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pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n",
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PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP));
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#endif /* CONFIG_HIGHMEM */
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#ifdef CONFIG_NOT_COHERENT_CACHE
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pr_info(" * 0x%08lx..0x%08lx : consistent mem\n",
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IOREMAP_TOP, IOREMAP_TOP + CONFIG_CONSISTENT_SIZE);
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#endif /* CONFIG_NOT_COHERENT_CACHE */
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pr_info(" * 0x%08lx..0x%08lx : early ioremap\n",
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ioremap_bot, IOREMAP_TOP);
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pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n",
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VMALLOC_START, VMALLOC_END);
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#endif /* CONFIG_PPC32 */
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mem_init_done = 1;
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}
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void free_initmem(void)
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{
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unsigned long addr;
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ppc_md.progress = ppc_printk_progress;
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addr = (unsigned long)__init_begin;
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for (; addr < (unsigned long)__init_end; addr += PAGE_SIZE) {
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memset((void *)addr, POISON_FREE_INITMEM, 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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pr_info("Freeing unused kernel memory: %luk freed\n",
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((unsigned long)__init_end -
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(unsigned long)__init_begin) >> 10);
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}
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#ifdef CONFIG_BLK_DEV_INITRD
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void __init free_initrd_mem(unsigned long start, unsigned long end)
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{
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if (start >= end)
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return;
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start = _ALIGN_DOWN(start, PAGE_SIZE);
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end = _ALIGN_UP(end, PAGE_SIZE);
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pr_info("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
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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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}
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}
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#endif
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/*
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* This is called when a page has been modified by the kernel.
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* It just marks the page as not i-cache clean. We do the i-cache
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* flush later when the page is given to a user process, if necessary.
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*/
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void flush_dcache_page(struct page *page)
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{
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if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
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return;
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/* avoid an atomic op if possible */
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if (test_bit(PG_arch_1, &page->flags))
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clear_bit(PG_arch_1, &page->flags);
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}
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EXPORT_SYMBOL(flush_dcache_page);
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void flush_dcache_icache_page(struct page *page)
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{
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#ifdef CONFIG_HUGETLB_PAGE
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if (PageCompound(page)) {
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flush_dcache_icache_hugepage(page);
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return;
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}
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#endif
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#ifdef CONFIG_BOOKE
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{
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void *start = kmap_atomic(page);
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__flush_dcache_icache(start);
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kunmap_atomic(start);
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}
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#elif defined(CONFIG_8xx) || defined(CONFIG_PPC64)
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/* On 8xx there is no need to kmap since highmem is not supported */
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__flush_dcache_icache(page_address(page));
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#else
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__flush_dcache_icache_phys(page_to_pfn(page) << PAGE_SHIFT);
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#endif
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}
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void clear_user_page(void *page, unsigned long vaddr, struct page *pg)
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{
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clear_page(page);
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/*
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* We shouldn't have to do this, but some versions of glibc
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* require it (ld.so assumes zero filled pages are icache clean)
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* - Anton
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*/
|
|
flush_dcache_page(pg);
|
|
}
|
|
EXPORT_SYMBOL(clear_user_page);
|
|
|
|
void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
|
|
struct page *pg)
|
|
{
|
|
copy_page(vto, vfrom);
|
|
|
|
/*
|
|
* We should be able to use the following optimisation, however
|
|
* there are two problems.
|
|
* Firstly a bug in some versions of binutils meant PLT sections
|
|
* were not marked executable.
|
|
* Secondly the first word in the GOT section is blrl, used
|
|
* to establish the GOT address. Until recently the GOT was
|
|
* not marked executable.
|
|
* - Anton
|
|
*/
|
|
#if 0
|
|
if (!vma->vm_file && ((vma->vm_flags & VM_EXEC) == 0))
|
|
return;
|
|
#endif
|
|
|
|
flush_dcache_page(pg);
|
|
}
|
|
|
|
void flush_icache_user_range(struct vm_area_struct *vma, struct page *page,
|
|
unsigned long addr, int len)
|
|
{
|
|
unsigned long maddr;
|
|
|
|
maddr = (unsigned long) kmap(page) + (addr & ~PAGE_MASK);
|
|
flush_icache_range(maddr, maddr + len);
|
|
kunmap(page);
|
|
}
|
|
EXPORT_SYMBOL(flush_icache_user_range);
|
|
|
|
/*
|
|
* This is called at the end of handling a user page fault, when the
|
|
* fault has been handled by updating a PTE in the linux page tables.
|
|
* We use it to preload an HPTE into the hash table corresponding to
|
|
* the updated linux PTE.
|
|
*
|
|
* This must always be called with the pte lock held.
|
|
*/
|
|
void update_mmu_cache(struct vm_area_struct *vma, unsigned long address,
|
|
pte_t *ptep)
|
|
{
|
|
#ifdef CONFIG_PPC_STD_MMU
|
|
unsigned long access = 0, trap;
|
|
|
|
/* We only want HPTEs for linux PTEs that have _PAGE_ACCESSED set */
|
|
if (!pte_young(*ptep) || address >= TASK_SIZE)
|
|
return;
|
|
|
|
/* We try to figure out if we are coming from an instruction
|
|
* access fault and pass that down to __hash_page so we avoid
|
|
* double-faulting on execution of fresh text. We have to test
|
|
* for regs NULL since init will get here first thing at boot
|
|
*
|
|
* We also avoid filling the hash if not coming from a fault
|
|
*/
|
|
if (current->thread.regs == NULL)
|
|
return;
|
|
trap = TRAP(current->thread.regs);
|
|
if (trap == 0x400)
|
|
access |= _PAGE_EXEC;
|
|
else if (trap != 0x300)
|
|
return;
|
|
hash_preload(vma->vm_mm, address, access, trap);
|
|
#endif /* CONFIG_PPC_STD_MMU */
|
|
#if (defined(CONFIG_PPC_BOOK3E_64) || defined(CONFIG_PPC_FSL_BOOK3E)) \
|
|
&& defined(CONFIG_HUGETLB_PAGE)
|
|
if (is_vm_hugetlb_page(vma))
|
|
book3e_hugetlb_preload(vma, address, *ptep);
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* System memory should not be in /proc/iomem but various tools expect it
|
|
* (eg kdump).
|
|
*/
|
|
static int add_system_ram_resources(void)
|
|
{
|
|
struct memblock_region *reg;
|
|
|
|
for_each_memblock(memory, reg) {
|
|
struct resource *res;
|
|
unsigned long base = reg->base;
|
|
unsigned long size = reg->size;
|
|
|
|
res = kzalloc(sizeof(struct resource), GFP_KERNEL);
|
|
WARN_ON(!res);
|
|
|
|
if (res) {
|
|
res->name = "System RAM";
|
|
res->start = base;
|
|
res->end = base + size - 1;
|
|
res->flags = IORESOURCE_MEM;
|
|
WARN_ON(request_resource(&iomem_resource, res) < 0);
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
subsys_initcall(add_system_ram_resources);
|
|
|
|
#ifdef CONFIG_STRICT_DEVMEM
|
|
/*
|
|
* devmem_is_allowed(): check to see if /dev/mem access to a certain address
|
|
* is valid. The argument is a physical page number.
|
|
*
|
|
* Access has to be given to non-kernel-ram areas as well, these contain the
|
|
* PCI mmio resources as well as potential bios/acpi data regions.
|
|
*/
|
|
int devmem_is_allowed(unsigned long pfn)
|
|
{
|
|
if (iomem_is_exclusive(pfn << PAGE_SHIFT))
|
|
return 0;
|
|
if (!page_is_ram(pfn))
|
|
return 1;
|
|
if (page_is_rtas_user_buf(pfn))
|
|
return 1;
|
|
return 0;
|
|
}
|
|
#endif /* CONFIG_STRICT_DEVMEM */
|