![David Hildenbrand](/assets/img/avatar_default.png)
We want to improve error handling while adding memory by allowing to use arch_remove_memory() and __remove_pages() even if CONFIG_MEMORY_HOTREMOVE is not set to e.g., implement something like: arch_add_memory() rc = do_something(); if (rc) { arch_remove_memory(); } We won't get rid of CONFIG_MEMORY_HOTREMOVE for now, as it will require quite some dependencies for memory offlining. Link: http://lkml.kernel.org/r/20190527111152.16324-7-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Rich Felker <dalias@libc.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: David Hildenbrand <david@redhat.com> Cc: Oscar Salvador <osalvador@suse.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Mark Brown <broonie@kernel.org> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Rob Herring <robh@kernel.org> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: "mike.travis@hpe.com" <mike.travis@hpe.com> Cc: Andrew Banman <andrew.banman@hpe.com> Cc: Arun KS <arunks@codeaurora.org> Cc: Qian Cai <cai@lca.pw> Cc: Mathieu Malaterre <malat@debian.org> Cc: Baoquan He <bhe@redhat.com> Cc: Logan Gunthorpe <logang@deltatee.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chintan Pandya <cpandya@codeaurora.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Jun Yao <yaojun8558363@gmail.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
520 lines
14 KiB
C
520 lines
14 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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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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#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/memblock.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/hugetlb.h>
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#include <linux/slab.h>
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#include <linux/vmalloc.h>
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#include <linux/memremap.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 <mm/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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unsigned long long memory_limit;
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bool init_mem_is_free;
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#ifdef CONFIG_HIGHMEM
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pte_t *kmap_pte;
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EXPORT_SYMBOL(kmap_pte);
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pgprot_t kmap_prot;
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EXPORT_SYMBOL(kmap_prot);
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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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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 __weak create_section_mapping(unsigned long start, unsigned long end, int nid)
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{
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return -ENODEV;
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}
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int __weak remove_section_mapping(unsigned long start, unsigned long end)
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{
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return -ENODEV;
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}
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int __ref arch_add_memory(int nid, u64 start, u64 size,
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struct mhp_restrictions *restrictions)
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{
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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 rc;
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resize_hpt_for_hotplug(memblock_phys_mem_size());
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start = (unsigned long)__va(start);
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rc = create_section_mapping(start, start + size, nid);
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if (rc) {
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pr_warn("Unable to create mapping for hot added memory 0x%llx..0x%llx: %d\n",
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start, start + size, rc);
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return -EFAULT;
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}
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flush_dcache_range(start, start + size);
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return __add_pages(nid, start_pfn, nr_pages, restrictions);
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}
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void __ref arch_remove_memory(int nid, u64 start, u64 size,
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struct vmem_altmap *altmap)
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{
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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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struct page *page = pfn_to_page(start_pfn) + vmem_altmap_offset(altmap);
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int ret;
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__remove_pages(page_zone(page), start_pfn, nr_pages, altmap);
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/* Remove htab bolted mappings for this section of memory */
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start = (unsigned long)__va(start);
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flush_dcache_range(start, start + size);
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ret = remove_section_mapping(start, start + size);
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WARN_ON_ONCE(ret);
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/* Ensure all vmalloc mappings are flushed in case they also
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* hit that section of memory
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*/
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vm_unmap_aliases();
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if (resize_hpt_for_hotplug(memblock_phys_mem_size()) == -ENOSPC)
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pr_warn("Hash collision while resizing HPT\n");
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}
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#endif
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#ifndef CONFIG_NEED_MULTIPLE_NODES
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void __init mem_topology_setup(void)
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{
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max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
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min_low_pfn = MEMORY_START >> PAGE_SHIFT;
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#ifdef CONFIG_HIGHMEM
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max_low_pfn = lowmem_end_addr >> PAGE_SHIFT;
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#endif
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/* Place all memblock_regions in the same node and merge contiguous
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* memblock_regions
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*/
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memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0);
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}
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void __init initmem_init(void)
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{
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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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sparse_init();
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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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#else /* CONFIG_NEED_MULTIPLE_NODES */
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static int __init mark_nonram_nosave(void)
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{
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return 0;
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}
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#endif
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/*
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* Zones usage:
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*
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* We setup ZONE_DMA to be 31-bits on all platforms and ZONE_NORMAL to be
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* everything else. GFP_DMA32 page allocations automatically fall back to
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* ZONE_DMA.
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*
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* By using 31-bit unconditionally, we can exploit ARCH_ZONE_DMA_BITS to
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* inform the generic DMA mapping code. 32-bit only devices (if not handled
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* by an IOMMU anyway) will take a first dip into ZONE_NORMAL and get
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* otherwise served by ZONE_DMA.
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*/
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static unsigned long max_zone_pfns[MAX_NR_ZONES];
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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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#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_kernel_page(v, 0, __pgprot(0)); /* XXX gross */
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#endif
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#ifdef CONFIG_HIGHMEM
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map_kernel_page(PKMAP_BASE, 0, __pgprot(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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#ifdef CONFIG_ZONE_DMA
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max_zone_pfns[ZONE_DMA] = min(max_low_pfn,
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((1UL << ARCH_ZONE_DMA_BITS) - 1) >> PAGE_SHIFT);
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#endif
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max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
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#ifdef CONFIG_HIGHMEM
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max_zone_pfns[ZONE_HIGHMEM] = max_pfn;
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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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void __init mem_init(void)
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{
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/*
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* book3s is limited to 16 page sizes due to encoding this in
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* a 4-bit field for slices.
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*/
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BUILD_BUG_ON(MMU_PAGE_COUNT > 16);
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#ifdef CONFIG_SWIOTLB
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swiotlb_init(0);
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#endif
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high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
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set_max_mapnr(max_pfn);
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memblock_free_all();
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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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free_highmem_page(page);
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}
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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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mem_init_print_info(NULL);
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#ifdef CONFIG_PPC32
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pr_info("Kernel virtual memory layout:\n");
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#ifdef CONFIG_KASAN
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pr_info(" * 0x%08lx..0x%08lx : kasan shadow mem\n",
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KASAN_SHADOW_START, KASAN_SHADOW_END);
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#endif
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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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}
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void free_initmem(void)
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{
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ppc_md.progress = ppc_printk_progress;
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mark_initmem_nx();
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init_mem_is_free = true;
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free_initmem_default(POISON_FREE_INITMEM);
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}
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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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#if defined(CONFIG_PPC_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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if (IS_ENABLED(CONFIG_BOOKE) || sizeof(phys_addr_t) > sizeof(void *)) {
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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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} else {
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__flush_dcache_icache_phys(page_to_pfn(page) << PAGE_SHIFT);
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}
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#endif
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}
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EXPORT_SYMBOL(flush_dcache_icache_page);
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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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*/
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flush_dcache_page(pg);
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}
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EXPORT_SYMBOL(clear_user_page);
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void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
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struct page *pg)
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{
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copy_page(vto, vfrom);
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/*
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* We should be able to use the following optimisation, however
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* there are two problems.
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* Firstly a bug in some versions of binutils meant PLT sections
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* were not marked executable.
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* Secondly the first word in the GOT section is blrl, used
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* to establish the GOT address. Until recently the GOT was
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* not marked executable.
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* - Anton
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*/
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#if 0
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if (!vma->vm_file && ((vma->vm_flags & VM_EXEC) == 0))
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return;
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#endif
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flush_dcache_page(pg);
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}
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void flush_icache_user_range(struct vm_area_struct *vma, struct page *page,
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unsigned long addr, int len)
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{
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unsigned long maddr;
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maddr = (unsigned long) kmap(page) + (addr & ~PAGE_MASK);
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flush_icache_range(maddr, maddr + len);
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kunmap(page);
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}
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EXPORT_SYMBOL(flush_icache_user_range);
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/*
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* This is called at the end of handling a user page fault, when the
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* fault has been handled by updating a PTE in the linux page tables.
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* We use it to preload an HPTE into the hash table corresponding to
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* the updated linux PTE.
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*
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* This must always be called with the pte lock held.
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|
*/
|
|
void update_mmu_cache(struct vm_area_struct *vma, unsigned long address,
|
|
pte_t *ptep)
|
|
{
|
|
#ifdef CONFIG_PPC_BOOK3S
|
|
/*
|
|
* We don't need to worry about _PAGE_PRESENT here because we are
|
|
* called with either mm->page_table_lock held or ptl lock held
|
|
*/
|
|
unsigned long trap;
|
|
bool is_exec;
|
|
|
|
if (radix_enabled()) {
|
|
prefetch((void *)address);
|
|
return;
|
|
}
|
|
|
|
/* 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
|
|
*/
|
|
|
|
trap = current->thread.regs ? TRAP(current->thread.regs) : 0UL;
|
|
switch (trap) {
|
|
case 0x300:
|
|
is_exec = false;
|
|
break;
|
|
case 0x400:
|
|
is_exec = true;
|
|
break;
|
|
default:
|
|
return;
|
|
}
|
|
|
|
hash_preload(vma->vm_mm, address, is_exec, trap);
|
|
#endif /* CONFIG_PPC_BOOK3S */
|
|
#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 __init 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_SYSTEM_RAM | IORESOURCE_BUSY;
|
|
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 (page_is_rtas_user_buf(pfn))
|
|
return 1;
|
|
if (iomem_is_exclusive(PFN_PHYS(pfn)))
|
|
return 0;
|
|
if (!page_is_ram(pfn))
|
|
return 1;
|
|
return 0;
|
|
}
|
|
#endif /* CONFIG_STRICT_DEVMEM */
|
|
|
|
/*
|
|
* This is defined in kernel/resource.c but only powerpc needs to export it, for
|
|
* the EHEA driver. Drop this when drivers/net/ethernet/ibm/ehea is removed.
|
|
*/
|
|
EXPORT_SYMBOL_GPL(walk_system_ram_range);
|