88f3aec7af
recently the 64-bit allyesconfig bzImage kernel started spontaneously
rebooting during early bootup.
after a few fun hours spent with early init debugging, it turns out
that we've got this rather annoying limit on the size of the kernel
image:
#define KERNEL_TEXT_SIZE (40*1024*1024)
which limit my vmlinux just happened to pass:
text data bss dec hex filename
29703744 4222751 8646224
42572719 2899baf vmlinux
40 MB is 42572719 bytes, so my vmlinux was just 1.5% above this limit :-/
So it happily crashed right in head_64.S, which - as we all know - is
the most debuggable code in the whole architecture ;-)
So increase the limit to allow an up to 128MB kernel image to be mapped.
(should anyone be that crazy or lazy)
We have a full 4K of pagetable (level2_kernel_pgt) allocated for these
mappings already, so there's no RAM overhead and the limit was rather
pointless and arbitrary.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
810 lines
19 KiB
C
810 lines
19 KiB
C
/*
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* linux/arch/x86_64/mm/init.c
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*
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* Copyright (C) 1995 Linus Torvalds
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* Copyright (C) 2000 Pavel Machek <pavel@suse.cz>
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* Copyright (C) 2002,2003 Andi Kleen <ak@suse.de>
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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/smp.h>
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#include <linux/init.h>
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#include <linux/pagemap.h>
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#include <linux/bootmem.h>
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#include <linux/proc_fs.h>
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#include <linux/pci.h>
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#include <linux/pfn.h>
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#include <linux/poison.h>
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#include <linux/dma-mapping.h>
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#include <linux/module.h>
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#include <linux/memory_hotplug.h>
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#include <linux/nmi.h>
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#include <asm/processor.h>
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#include <asm/system.h>
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#include <asm/uaccess.h>
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#include <asm/pgtable.h>
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#include <asm/pgalloc.h>
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#include <asm/dma.h>
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#include <asm/fixmap.h>
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#include <asm/e820.h>
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#include <asm/apic.h>
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#include <asm/tlb.h>
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#include <asm/mmu_context.h>
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#include <asm/proto.h>
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#include <asm/smp.h>
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#include <asm/sections.h>
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#include <asm/kdebug.h>
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#include <asm/numa.h>
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#include <asm/cacheflush.h>
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const struct dma_mapping_ops *dma_ops;
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EXPORT_SYMBOL(dma_ops);
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static unsigned long dma_reserve __initdata;
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DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
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/*
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* NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
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* physical space so we can cache the place of the first one and move
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* around without checking the pgd every time.
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*/
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void show_mem(void)
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{
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long i, total = 0, reserved = 0;
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long shared = 0, cached = 0;
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struct page *page;
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pg_data_t *pgdat;
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printk(KERN_INFO "Mem-info:\n");
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show_free_areas();
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printk(KERN_INFO "Free swap: %6ldkB\n",
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nr_swap_pages << (PAGE_SHIFT-10));
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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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/*
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* This loop can take a while with 256 GB and
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* 4k pages so defer the NMI watchdog:
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*/
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if (unlikely(i % MAX_ORDER_NR_PAGES == 0))
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touch_nmi_watchdog();
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if (!pfn_valid(pgdat->node_start_pfn + i))
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continue;
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page = pfn_to_page(pgdat->node_start_pfn + i);
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total++;
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if (PageReserved(page))
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reserved++;
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else if (PageSwapCache(page))
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cached++;
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else if (page_count(page))
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shared += page_count(page) - 1;
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}
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}
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printk(KERN_INFO "%lu pages of RAM\n", total);
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printk(KERN_INFO "%lu reserved pages\n", reserved);
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printk(KERN_INFO "%lu pages shared\n", shared);
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printk(KERN_INFO "%lu pages swap cached\n", cached);
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}
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int after_bootmem;
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static __init void *spp_getpage(void)
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{
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void *ptr;
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if (after_bootmem)
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ptr = (void *) get_zeroed_page(GFP_ATOMIC);
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else
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ptr = alloc_bootmem_pages(PAGE_SIZE);
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if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
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panic("set_pte_phys: cannot allocate page data %s\n",
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after_bootmem ? "after bootmem" : "");
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}
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pr_debug("spp_getpage %p\n", ptr);
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return ptr;
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}
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static __init void
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set_pte_phys(unsigned long vaddr, unsigned long phys, pgprot_t prot)
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{
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pgd_t *pgd;
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pud_t *pud;
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pmd_t *pmd;
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pte_t *pte, new_pte;
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pr_debug("set_pte_phys %lx to %lx\n", vaddr, phys);
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pgd = pgd_offset_k(vaddr);
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if (pgd_none(*pgd)) {
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printk(KERN_ERR
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"PGD FIXMAP MISSING, it should be setup in head.S!\n");
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return;
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}
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pud = pud_offset(pgd, vaddr);
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if (pud_none(*pud)) {
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pmd = (pmd_t *) spp_getpage();
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set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE | _PAGE_USER));
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if (pmd != pmd_offset(pud, 0)) {
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printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
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pmd, pmd_offset(pud, 0));
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return;
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}
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}
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pmd = pmd_offset(pud, vaddr);
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if (pmd_none(*pmd)) {
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pte = (pte_t *) spp_getpage();
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set_pmd(pmd, __pmd(__pa(pte) | _KERNPG_TABLE | _PAGE_USER));
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if (pte != pte_offset_kernel(pmd, 0)) {
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printk(KERN_ERR "PAGETABLE BUG #02!\n");
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return;
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}
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}
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new_pte = pfn_pte(phys >> PAGE_SHIFT, prot);
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pte = pte_offset_kernel(pmd, vaddr);
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if (!pte_none(*pte) &&
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pte_val(*pte) != (pte_val(new_pte) & __supported_pte_mask))
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pte_ERROR(*pte);
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set_pte(pte, new_pte);
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/*
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* It's enough to flush this one mapping.
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* (PGE mappings get flushed as well)
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*/
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__flush_tlb_one(vaddr);
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}
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/*
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* The head.S code sets up the kernel high mapping:
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*
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* from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
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*
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* phys_addr holds the negative offset to the kernel, which is added
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* to the compile time generated pmds. This results in invalid pmds up
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* to the point where we hit the physaddr 0 mapping.
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*
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* We limit the mappings to the region from _text to _end. _end is
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* rounded up to the 2MB boundary. This catches the invalid pmds as
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* well, as they are located before _text:
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*/
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void __init cleanup_highmap(void)
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{
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unsigned long vaddr = __START_KERNEL_map;
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unsigned long end = round_up((unsigned long)_end, PMD_SIZE) - 1;
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pmd_t *pmd = level2_kernel_pgt;
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pmd_t *last_pmd = pmd + PTRS_PER_PMD;
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for (; pmd < last_pmd; pmd++, vaddr += PMD_SIZE) {
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if (!pmd_present(*pmd))
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continue;
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if (vaddr < (unsigned long) _text || vaddr > end)
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set_pmd(pmd, __pmd(0));
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}
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}
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/* NOTE: this is meant to be run only at boot */
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void __init
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__set_fixmap(enum fixed_addresses idx, unsigned long phys, pgprot_t prot)
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{
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unsigned long address = __fix_to_virt(idx);
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if (idx >= __end_of_fixed_addresses) {
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printk(KERN_ERR "Invalid __set_fixmap\n");
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return;
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}
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set_pte_phys(address, phys, prot);
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}
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static unsigned long __initdata table_start;
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static unsigned long __meminitdata table_end;
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static __meminit void *alloc_low_page(unsigned long *phys)
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{
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unsigned long pfn = table_end++;
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void *adr;
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if (after_bootmem) {
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adr = (void *)get_zeroed_page(GFP_ATOMIC);
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*phys = __pa(adr);
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return adr;
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}
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if (pfn >= end_pfn)
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panic("alloc_low_page: ran out of memory");
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adr = early_ioremap(pfn * PAGE_SIZE, PAGE_SIZE);
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memset(adr, 0, PAGE_SIZE);
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*phys = pfn * PAGE_SIZE;
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return adr;
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}
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static __meminit void unmap_low_page(void *adr)
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{
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if (after_bootmem)
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return;
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early_iounmap(adr, PAGE_SIZE);
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}
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/* Must run before zap_low_mappings */
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__meminit void *early_ioremap(unsigned long addr, unsigned long size)
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{
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pmd_t *pmd, *last_pmd;
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unsigned long vaddr;
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int i, pmds;
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pmds = ((addr & ~PMD_MASK) + size + ~PMD_MASK) / PMD_SIZE;
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vaddr = __START_KERNEL_map;
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pmd = level2_kernel_pgt;
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last_pmd = level2_kernel_pgt + PTRS_PER_PMD - 1;
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for (; pmd <= last_pmd; pmd++, vaddr += PMD_SIZE) {
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for (i = 0; i < pmds; i++) {
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if (pmd_present(pmd[i]))
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goto continue_outer_loop;
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}
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vaddr += addr & ~PMD_MASK;
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addr &= PMD_MASK;
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for (i = 0; i < pmds; i++, addr += PMD_SIZE)
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set_pmd(pmd+i, __pmd(addr | __PAGE_KERNEL_LARGE_EXEC));
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__flush_tlb_all();
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return (void *)vaddr;
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continue_outer_loop:
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;
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}
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printk(KERN_ERR "early_ioremap(0x%lx, %lu) failed\n", addr, size);
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return NULL;
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}
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/*
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* To avoid virtual aliases later:
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*/
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__meminit void early_iounmap(void *addr, unsigned long size)
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{
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unsigned long vaddr;
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pmd_t *pmd;
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int i, pmds;
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vaddr = (unsigned long)addr;
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pmds = ((vaddr & ~PMD_MASK) + size + ~PMD_MASK) / PMD_SIZE;
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pmd = level2_kernel_pgt + pmd_index(vaddr);
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for (i = 0; i < pmds; i++)
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pmd_clear(pmd + i);
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__flush_tlb_all();
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}
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static void __meminit
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phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end)
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{
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int i = pmd_index(address);
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for (; i < PTRS_PER_PMD; i++, address += PMD_SIZE) {
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pmd_t *pmd = pmd_page + pmd_index(address);
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if (address >= end) {
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if (!after_bootmem) {
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for (; i < PTRS_PER_PMD; i++, pmd++)
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set_pmd(pmd, __pmd(0));
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}
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break;
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}
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if (pmd_val(*pmd))
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continue;
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set_pte((pte_t *)pmd,
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pfn_pte(address >> PAGE_SHIFT, PAGE_KERNEL_LARGE));
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}
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}
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static void __meminit
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phys_pmd_update(pud_t *pud, unsigned long address, unsigned long end)
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{
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pmd_t *pmd = pmd_offset(pud, 0);
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spin_lock(&init_mm.page_table_lock);
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phys_pmd_init(pmd, address, end);
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spin_unlock(&init_mm.page_table_lock);
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__flush_tlb_all();
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}
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static void __meminit
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phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end)
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{
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int i = pud_index(addr);
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for (; i < PTRS_PER_PUD; i++, addr = (addr & PUD_MASK) + PUD_SIZE) {
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unsigned long pmd_phys;
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pud_t *pud = pud_page + pud_index(addr);
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pmd_t *pmd;
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if (addr >= end)
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break;
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if (!after_bootmem &&
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!e820_any_mapped(addr, addr+PUD_SIZE, 0)) {
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set_pud(pud, __pud(0));
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continue;
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}
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if (pud_val(*pud)) {
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phys_pmd_update(pud, addr, end);
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continue;
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}
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pmd = alloc_low_page(&pmd_phys);
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spin_lock(&init_mm.page_table_lock);
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set_pud(pud, __pud(pmd_phys | _KERNPG_TABLE));
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phys_pmd_init(pmd, addr, end);
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spin_unlock(&init_mm.page_table_lock);
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unmap_low_page(pmd);
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}
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__flush_tlb_all();
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}
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static void __init find_early_table_space(unsigned long end)
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{
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unsigned long puds, pmds, tables, start;
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puds = (end + PUD_SIZE - 1) >> PUD_SHIFT;
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pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT;
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tables = round_up(puds * sizeof(pud_t), PAGE_SIZE) +
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round_up(pmds * sizeof(pmd_t), PAGE_SIZE);
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/*
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* RED-PEN putting page tables only on node 0 could
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* cause a hotspot and fill up ZONE_DMA. The page tables
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* need roughly 0.5KB per GB.
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*/
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start = 0x8000;
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table_start = find_e820_area(start, end, tables, PAGE_SIZE);
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if (table_start == -1UL)
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panic("Cannot find space for the kernel page tables");
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table_start >>= PAGE_SHIFT;
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table_end = table_start;
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early_printk("kernel direct mapping tables up to %lx @ %lx-%lx\n",
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end, table_start << PAGE_SHIFT,
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(table_start << PAGE_SHIFT) + tables);
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}
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/*
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* Setup the direct mapping of the physical memory at PAGE_OFFSET.
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* This runs before bootmem is initialized and gets pages directly from
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* the physical memory. To access them they are temporarily mapped.
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*/
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void __init_refok init_memory_mapping(unsigned long start, unsigned long end)
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{
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unsigned long next;
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pr_debug("init_memory_mapping\n");
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/*
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* Find space for the kernel direct mapping tables.
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*
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* Later we should allocate these tables in the local node of the
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* memory mapped. Unfortunately this is done currently before the
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* nodes are discovered.
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*/
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if (!after_bootmem)
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find_early_table_space(end);
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start = (unsigned long)__va(start);
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end = (unsigned long)__va(end);
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for (; start < end; start = next) {
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pgd_t *pgd = pgd_offset_k(start);
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unsigned long pud_phys;
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pud_t *pud;
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if (after_bootmem)
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pud = pud_offset(pgd, start & PGDIR_MASK);
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else
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pud = alloc_low_page(&pud_phys);
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next = start + PGDIR_SIZE;
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if (next > end)
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next = end;
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phys_pud_init(pud, __pa(start), __pa(next));
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if (!after_bootmem)
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set_pgd(pgd_offset_k(start), mk_kernel_pgd(pud_phys));
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unmap_low_page(pud);
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}
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if (!after_bootmem)
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mmu_cr4_features = read_cr4();
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__flush_tlb_all();
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if (!after_bootmem)
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reserve_early(table_start << PAGE_SHIFT,
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table_end << PAGE_SHIFT, "PGTABLE");
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}
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#ifndef CONFIG_NUMA
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void __init paging_init(void)
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{
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unsigned long max_zone_pfns[MAX_NR_ZONES];
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memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
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max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
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max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
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max_zone_pfns[ZONE_NORMAL] = end_pfn;
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memory_present(0, 0, end_pfn);
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sparse_init();
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free_area_init_nodes(max_zone_pfns);
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}
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#endif
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/*
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* Memory hotplug specific functions
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*/
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void online_page(struct page *page)
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{
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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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totalram_pages++;
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num_physpages++;
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}
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#ifdef CONFIG_MEMORY_HOTPLUG
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/*
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* Memory is added always to NORMAL zone. This means you will never get
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* additional DMA/DMA32 memory.
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*/
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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 *pgdat = NODE_DATA(nid);
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struct zone *zone = pgdat->node_zones + ZONE_NORMAL;
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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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int ret;
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init_memory_mapping(start, start + size-1);
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ret = __add_pages(zone, start_pfn, nr_pages);
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WARN_ON(1);
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return ret;
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}
|
|
EXPORT_SYMBOL_GPL(arch_add_memory);
|
|
|
|
#if !defined(CONFIG_ACPI_NUMA) && defined(CONFIG_NUMA)
|
|
int memory_add_physaddr_to_nid(u64 start)
|
|
{
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
|
|
#endif
|
|
|
|
#endif /* CONFIG_MEMORY_HOTPLUG */
|
|
|
|
static struct kcore_list kcore_mem, kcore_vmalloc, kcore_kernel,
|
|
kcore_modules, kcore_vsyscall;
|
|
|
|
void __init mem_init(void)
|
|
{
|
|
long codesize, reservedpages, datasize, initsize;
|
|
|
|
pci_iommu_alloc();
|
|
|
|
/* clear_bss() already clear the empty_zero_page */
|
|
|
|
reservedpages = 0;
|
|
|
|
/* this will put all low memory onto the freelists */
|
|
#ifdef CONFIG_NUMA
|
|
totalram_pages = numa_free_all_bootmem();
|
|
#else
|
|
totalram_pages = free_all_bootmem();
|
|
#endif
|
|
reservedpages = end_pfn - totalram_pages -
|
|
absent_pages_in_range(0, end_pfn);
|
|
after_bootmem = 1;
|
|
|
|
codesize = (unsigned long) &_etext - (unsigned long) &_text;
|
|
datasize = (unsigned long) &_edata - (unsigned long) &_etext;
|
|
initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
|
|
|
|
/* Register memory areas for /proc/kcore */
|
|
kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
|
|
kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
|
|
VMALLOC_END-VMALLOC_START);
|
|
kclist_add(&kcore_kernel, &_stext, _end - _stext);
|
|
kclist_add(&kcore_modules, (void *)MODULES_VADDR, MODULES_LEN);
|
|
kclist_add(&kcore_vsyscall, (void *)VSYSCALL_START,
|
|
VSYSCALL_END - VSYSCALL_START);
|
|
|
|
printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
|
|
"%ldk reserved, %ldk data, %ldk init)\n",
|
|
(unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
|
|
end_pfn << (PAGE_SHIFT-10),
|
|
codesize >> 10,
|
|
reservedpages << (PAGE_SHIFT-10),
|
|
datasize >> 10,
|
|
initsize >> 10);
|
|
|
|
cpa_init();
|
|
}
|
|
|
|
void free_init_pages(char *what, unsigned long begin, unsigned long end)
|
|
{
|
|
unsigned long addr = begin;
|
|
|
|
if (addr >= end)
|
|
return;
|
|
|
|
/*
|
|
* If debugging page accesses then do not free this memory but
|
|
* mark them not present - any buggy init-section access will
|
|
* create a kernel page fault:
|
|
*/
|
|
#ifdef CONFIG_DEBUG_PAGEALLOC
|
|
printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n",
|
|
begin, PAGE_ALIGN(end));
|
|
set_memory_np(begin, (end - begin) >> PAGE_SHIFT);
|
|
#else
|
|
printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);
|
|
|
|
for (; addr < end; addr += PAGE_SIZE) {
|
|
ClearPageReserved(virt_to_page(addr));
|
|
init_page_count(virt_to_page(addr));
|
|
memset((void *)(addr & ~(PAGE_SIZE-1)),
|
|
POISON_FREE_INITMEM, PAGE_SIZE);
|
|
free_page(addr);
|
|
totalram_pages++;
|
|
}
|
|
#endif
|
|
}
|
|
|
|
void free_initmem(void)
|
|
{
|
|
free_init_pages("unused kernel memory",
|
|
(unsigned long)(&__init_begin),
|
|
(unsigned long)(&__init_end));
|
|
}
|
|
|
|
#ifdef CONFIG_DEBUG_RODATA
|
|
const int rodata_test_data = 0xC3;
|
|
EXPORT_SYMBOL_GPL(rodata_test_data);
|
|
|
|
void mark_rodata_ro(void)
|
|
{
|
|
unsigned long start = (unsigned long)_stext, end;
|
|
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
/* It must still be possible to apply SMP alternatives. */
|
|
if (num_possible_cpus() > 1)
|
|
start = (unsigned long)_etext;
|
|
#endif
|
|
|
|
#ifdef CONFIG_KPROBES
|
|
start = (unsigned long)__start_rodata;
|
|
#endif
|
|
|
|
end = (unsigned long)__end_rodata;
|
|
start = (start + PAGE_SIZE - 1) & PAGE_MASK;
|
|
end &= PAGE_MASK;
|
|
if (end <= start)
|
|
return;
|
|
|
|
|
|
printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
|
|
(end - start) >> 10);
|
|
set_memory_ro(start, (end - start) >> PAGE_SHIFT);
|
|
|
|
/*
|
|
* The rodata section (but not the kernel text!) should also be
|
|
* not-executable.
|
|
*/
|
|
start = ((unsigned long)__start_rodata + PAGE_SIZE - 1) & PAGE_MASK;
|
|
set_memory_nx(start, (end - start) >> PAGE_SHIFT);
|
|
|
|
rodata_test();
|
|
|
|
#ifdef CONFIG_CPA_DEBUG
|
|
printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
|
|
set_memory_rw(start, (end-start) >> PAGE_SHIFT);
|
|
|
|
printk(KERN_INFO "Testing CPA: again\n");
|
|
set_memory_ro(start, (end-start) >> PAGE_SHIFT);
|
|
#endif
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_BLK_DEV_INITRD
|
|
void free_initrd_mem(unsigned long start, unsigned long end)
|
|
{
|
|
free_init_pages("initrd memory", start, end);
|
|
}
|
|
#endif
|
|
|
|
void __init reserve_bootmem_generic(unsigned long phys, unsigned len)
|
|
{
|
|
#ifdef CONFIG_NUMA
|
|
int nid = phys_to_nid(phys);
|
|
#endif
|
|
unsigned long pfn = phys >> PAGE_SHIFT;
|
|
|
|
if (pfn >= end_pfn) {
|
|
/*
|
|
* This can happen with kdump kernels when accessing
|
|
* firmware tables:
|
|
*/
|
|
if (pfn < end_pfn_map)
|
|
return;
|
|
|
|
printk(KERN_ERR "reserve_bootmem: illegal reserve %lx %u\n",
|
|
phys, len);
|
|
return;
|
|
}
|
|
|
|
/* Should check here against the e820 map to avoid double free */
|
|
#ifdef CONFIG_NUMA
|
|
reserve_bootmem_node(NODE_DATA(nid), phys, len, BOOTMEM_DEFAULT);
|
|
#else
|
|
reserve_bootmem(phys, len, BOOTMEM_DEFAULT);
|
|
#endif
|
|
if (phys+len <= MAX_DMA_PFN*PAGE_SIZE) {
|
|
dma_reserve += len / PAGE_SIZE;
|
|
set_dma_reserve(dma_reserve);
|
|
}
|
|
}
|
|
|
|
int kern_addr_valid(unsigned long addr)
|
|
{
|
|
unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
|
|
pgd_t *pgd;
|
|
pud_t *pud;
|
|
pmd_t *pmd;
|
|
pte_t *pte;
|
|
|
|
if (above != 0 && above != -1UL)
|
|
return 0;
|
|
|
|
pgd = pgd_offset_k(addr);
|
|
if (pgd_none(*pgd))
|
|
return 0;
|
|
|
|
pud = pud_offset(pgd, addr);
|
|
if (pud_none(*pud))
|
|
return 0;
|
|
|
|
pmd = pmd_offset(pud, addr);
|
|
if (pmd_none(*pmd))
|
|
return 0;
|
|
|
|
if (pmd_large(*pmd))
|
|
return pfn_valid(pmd_pfn(*pmd));
|
|
|
|
pte = pte_offset_kernel(pmd, addr);
|
|
if (pte_none(*pte))
|
|
return 0;
|
|
|
|
return pfn_valid(pte_pfn(*pte));
|
|
}
|
|
|
|
/*
|
|
* A pseudo VMA to allow ptrace access for the vsyscall page. This only
|
|
* covers the 64bit vsyscall page now. 32bit has a real VMA now and does
|
|
* not need special handling anymore:
|
|
*/
|
|
static struct vm_area_struct gate_vma = {
|
|
.vm_start = VSYSCALL_START,
|
|
.vm_end = VSYSCALL_START + (VSYSCALL_MAPPED_PAGES * PAGE_SIZE),
|
|
.vm_page_prot = PAGE_READONLY_EXEC,
|
|
.vm_flags = VM_READ | VM_EXEC
|
|
};
|
|
|
|
struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
|
|
{
|
|
#ifdef CONFIG_IA32_EMULATION
|
|
if (test_tsk_thread_flag(tsk, TIF_IA32))
|
|
return NULL;
|
|
#endif
|
|
return &gate_vma;
|
|
}
|
|
|
|
int in_gate_area(struct task_struct *task, unsigned long addr)
|
|
{
|
|
struct vm_area_struct *vma = get_gate_vma(task);
|
|
|
|
if (!vma)
|
|
return 0;
|
|
|
|
return (addr >= vma->vm_start) && (addr < vma->vm_end);
|
|
}
|
|
|
|
/*
|
|
* Use this when you have no reliable task/vma, typically from interrupt
|
|
* context. It is less reliable than using the task's vma and may give
|
|
* false positives:
|
|
*/
|
|
int in_gate_area_no_task(unsigned long addr)
|
|
{
|
|
return (addr >= VSYSCALL_START) && (addr < VSYSCALL_END);
|
|
}
|
|
|
|
const char *arch_vma_name(struct vm_area_struct *vma)
|
|
{
|
|
if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso)
|
|
return "[vdso]";
|
|
if (vma == &gate_vma)
|
|
return "[vsyscall]";
|
|
return NULL;
|
|
}
|
|
|
|
#ifdef CONFIG_SPARSEMEM_VMEMMAP
|
|
/*
|
|
* Initialise the sparsemem vmemmap using huge-pages at the PMD level.
|
|
*/
|
|
int __meminit
|
|
vmemmap_populate(struct page *start_page, unsigned long size, int node)
|
|
{
|
|
unsigned long addr = (unsigned long)start_page;
|
|
unsigned long end = (unsigned long)(start_page + size);
|
|
unsigned long next;
|
|
pgd_t *pgd;
|
|
pud_t *pud;
|
|
pmd_t *pmd;
|
|
|
|
for (; addr < end; addr = next) {
|
|
next = pmd_addr_end(addr, end);
|
|
|
|
pgd = vmemmap_pgd_populate(addr, node);
|
|
if (!pgd)
|
|
return -ENOMEM;
|
|
|
|
pud = vmemmap_pud_populate(pgd, addr, node);
|
|
if (!pud)
|
|
return -ENOMEM;
|
|
|
|
pmd = pmd_offset(pud, addr);
|
|
if (pmd_none(*pmd)) {
|
|
pte_t entry;
|
|
void *p;
|
|
|
|
p = vmemmap_alloc_block(PMD_SIZE, node);
|
|
if (!p)
|
|
return -ENOMEM;
|
|
|
|
entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
|
|
PAGE_KERNEL_LARGE);
|
|
set_pmd(pmd, __pmd(pte_val(entry)));
|
|
|
|
printk(KERN_DEBUG " [%lx-%lx] PMD ->%p on node %d\n",
|
|
addr, addr + PMD_SIZE - 1, p, node);
|
|
} else {
|
|
vmemmap_verify((pte_t *)pmd, node, addr, next);
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
#endif
|