645 lines
16 KiB
C
645 lines
16 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 <linux/dma-direct.h>
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#include <linux/kprobes.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/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 <asm/kasan.h>
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#include <asm/svm.h>
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#include <asm/mmzone.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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#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,
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int nid, pgprot_t prot)
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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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#define FLUSH_CHUNK_SIZE SZ_1G
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/**
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* flush_dcache_range_chunked(): Write any modified data cache blocks out to
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* memory and invalidate them, in chunks of up to FLUSH_CHUNK_SIZE
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* Does not invalidate the corresponding instruction cache blocks.
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*
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* @start: the start address
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* @stop: the stop address (exclusive)
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* @chunk: the max size of the chunks
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*/
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static void flush_dcache_range_chunked(unsigned long start, unsigned long stop,
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unsigned long chunk)
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{
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unsigned long i;
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for (i = start; i < stop; i += chunk) {
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flush_dcache_range(i, min(stop, i + chunk));
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cond_resched();
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}
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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_params *params)
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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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start = (unsigned long)__va(start);
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rc = create_section_mapping(start, start + size, nid,
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params->pgprot);
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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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return __add_pages(nid, start_pfn, nr_pages, params);
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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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int ret;
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__remove_pages(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_chunked(start, start + size, FLUSH_CHUNK_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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}
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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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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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unsigned long spfn, epfn, prev = 0;
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int i;
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for_each_mem_pfn_range(i, MAX_NUMNODES, &spfn, &epfn, NULL) {
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if (prev && prev < spfn)
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register_nosave_region(prev, spfn);
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prev = epfn;
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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 zone_dma_bits to inform the
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* generic DMA mapping code. 32-bit only devices (if not handled by an IOMMU
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* anyway) will take a first dip into ZONE_NORMAL and get otherwise served by
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* 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_HIGHMEM
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unsigned long v = __fix_to_virt(FIX_KMAP_END);
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unsigned long end = __fix_to_virt(FIX_KMAP_BEGIN);
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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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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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#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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/*
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* Allow 30-bit DMA for very limited Broadcom wifi chips on many
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* powerbooks.
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*/
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if (IS_ENABLED(CONFIG_PPC32))
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zone_dma_bits = 30;
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else
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zone_dma_bits = 31;
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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 << (zone_dma_bits - 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(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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/*
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* Some platforms (e.g. 85xx) limit DMA-able memory way below
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* 4G. We force memblock to bottom-up mode to ensure that the
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* memory allocated in swiotlb_init() is DMA-able.
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* As it's the last memblock allocation, no need to reset it
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* back to to-down.
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*/
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memblock_set_bottom_up(true);
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if (is_secure_guest())
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svm_swiotlb_init();
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else
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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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kasan_late_init();
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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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if (ioremap_bot != IOREMAP_TOP)
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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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* flush_coherent_icache() - if a CPU has a coherent icache, flush it
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* @addr: The base address to use (can be any valid address, the whole cache will be flushed)
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* Return true if the cache was flushed, false otherwise
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*/
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static inline bool flush_coherent_icache(unsigned long addr)
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{
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/*
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* For a snooping icache, we still need a dummy icbi to purge all the
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* prefetched instructions from the ifetch buffers. We also need a sync
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* before the icbi to order the the actual stores to memory that might
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* have modified instructions with the icbi.
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*/
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if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) {
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mb(); /* sync */
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allow_read_from_user((const void __user *)addr, L1_CACHE_BYTES);
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icbi((void *)addr);
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prevent_read_from_user((const void __user *)addr, L1_CACHE_BYTES);
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mb(); /* sync */
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isync();
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return true;
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}
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return false;
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}
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/**
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* invalidate_icache_range() - Flush the icache by issuing icbi across an address range
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* @start: the start address
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* @stop: the stop address (exclusive)
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*/
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static void invalidate_icache_range(unsigned long start, unsigned long stop)
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{
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unsigned long shift = l1_icache_shift();
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unsigned long bytes = l1_icache_bytes();
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char *addr = (char *)(start & ~(bytes - 1));
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unsigned long size = stop - (unsigned long)addr + (bytes - 1);
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unsigned long i;
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for (i = 0; i < size >> shift; i++, addr += bytes)
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icbi(addr);
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mb(); /* sync */
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isync();
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}
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/**
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* flush_icache_range: Write any modified data cache blocks out to memory
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* and invalidate the corresponding blocks in the instruction cache
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*
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* Generic code will call this after writing memory, before executing from it.
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*
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* @start: the start address
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* @stop: the stop address (exclusive)
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*/
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void flush_icache_range(unsigned long start, unsigned long stop)
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{
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if (flush_coherent_icache(start))
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return;
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clean_dcache_range(start, stop);
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if (IS_ENABLED(CONFIG_44x)) {
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/*
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* Flash invalidate on 44x because we are passed kmapped
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* addresses and this doesn't work for userspace pages due to
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* the virtually tagged icache.
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*/
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iccci((void *)start);
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mb(); /* sync */
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isync();
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} else
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invalidate_icache_range(start, stop);
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}
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EXPORT_SYMBOL(flush_icache_range);
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#if !defined(CONFIG_PPC_8xx) && !defined(CONFIG_PPC64)
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/**
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* flush_dcache_icache_phys() - Flush a page by it's physical address
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* @physaddr: the physical address of the page
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*/
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static void flush_dcache_icache_phys(unsigned long physaddr)
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{
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unsigned long bytes = l1_dcache_bytes();
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unsigned long nb = PAGE_SIZE / bytes;
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unsigned long addr = physaddr & PAGE_MASK;
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unsigned long msr, msr0;
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unsigned long loop1 = addr, loop2 = addr;
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msr0 = mfmsr();
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msr = msr0 & ~MSR_DR;
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/*
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* This must remain as ASM to prevent potential memory accesses
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* while the data MMU is disabled
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*/
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asm volatile(
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" mtctr %2;\n"
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" mtmsr %3;\n"
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" isync;\n"
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"0: dcbst 0, %0;\n"
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" addi %0, %0, %4;\n"
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" bdnz 0b;\n"
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" sync;\n"
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" mtctr %2;\n"
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"1: icbi 0, %1;\n"
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" addi %1, %1, %4;\n"
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" bdnz 1b;\n"
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" sync;\n"
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" mtmsr %5;\n"
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" isync;\n"
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: "+&r" (loop1), "+&r" (loop2)
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: "r" (nb), "r" (msr), "i" (bytes), "r" (msr0)
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: "ctr", "memory");
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}
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NOKPROBE_SYMBOL(flush_dcache_icache_phys)
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#endif // !defined(CONFIG_PPC_8xx) && !defined(CONFIG_PPC64)
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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);
|
|
__flush_dcache_icache(start);
|
|
kunmap_atomic(start);
|
|
} else {
|
|
unsigned long addr = page_to_pfn(page) << PAGE_SHIFT;
|
|
|
|
if (flush_coherent_icache(addr))
|
|
return;
|
|
flush_dcache_icache_phys(addr);
|
|
}
|
|
#endif
|
|
}
|
|
EXPORT_SYMBOL(flush_dcache_icache_page);
|
|
|
|
/**
|
|
* __flush_dcache_icache(): Flush a particular page from the data cache to RAM.
|
|
* Note: this is necessary because the instruction cache does *not*
|
|
* snoop from the data cache.
|
|
*
|
|
* @page: the address of the page to flush
|
|
*/
|
|
void __flush_dcache_icache(void *p)
|
|
{
|
|
unsigned long addr = (unsigned long)p;
|
|
|
|
if (flush_coherent_icache(addr))
|
|
return;
|
|
|
|
clean_dcache_range(addr, addr + PAGE_SIZE);
|
|
|
|
/*
|
|
* We don't flush the icache on 44x. Those have a virtual icache and we
|
|
* don't have access to the virtual address here (it's not the page
|
|
* vaddr but where it's mapped in user space). The flushing of the
|
|
* icache on these is handled elsewhere, when a change in the address
|
|
* space occurs, before returning to user space.
|
|
*/
|
|
|
|
if (cpu_has_feature(MMU_FTR_TYPE_44x))
|
|
return;
|
|
|
|
invalidate_icache_range(addr, addr + PAGE_SIZE);
|
|
}
|
|
|
|
void clear_user_page(void *page, unsigned long vaddr, struct page *pg)
|
|
{
|
|
clear_page(page);
|
|
|
|
/*
|
|
* We shouldn't have to do this, but some versions of glibc
|
|
* require it (ld.so assumes zero filled pages are icache clean)
|
|
* - Anton
|
|
*/
|
|
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_page(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);
|
|
}
|
|
|
|
/*
|
|
* System memory should not be in /proc/iomem but various tools expect it
|
|
* (eg kdump).
|
|
*/
|
|
static int __init add_system_ram_resources(void)
|
|
{
|
|
phys_addr_t start, end;
|
|
u64 i;
|
|
|
|
for_each_mem_range(i, &start, &end) {
|
|
struct resource *res;
|
|
|
|
res = kzalloc(sizeof(struct resource), GFP_KERNEL);
|
|
WARN_ON(!res);
|
|
|
|
if (res) {
|
|
res->name = "System RAM";
|
|
res->start = start;
|
|
/*
|
|
* In memblock, end points to the first byte after
|
|
* the range while in resourses, end points to the
|
|
* last byte in the range.
|
|
*/
|
|
res->end = end - 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);
|