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	Add a m68k-only set_fc helper to set the SFC and DFC registers for the few places that need to override it for special MM operations, but disconnect that from the deprecated kernel-wide set_fs() API. Note that the SFC/DFC registers are context switched, so there is no need to disable preemption. Partially based on an earlier patch from Linus Torvalds <torvalds@linux-foundation.org>. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Michael Schmitz <schmitzmic@gmail.com> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Link: https://lore.kernel.org/r/20210916070405.52750-7-hch@lst.de Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
		
			
				
	
	
		
			130 lines
		
	
	
	
		
			2.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			130 lines
		
	
	
	
		
			2.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
// SPDX-License-Identifier: GPL-2.0
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/*
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 *  linux/arch/m68k/mm/init.c
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 *
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 *  Copyright (C) 1995  Hamish Macdonald
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 *
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 *  Contains common initialization routines, specific init code moved
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 *  to motorola.c and sun3mmu.c
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 */
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#include <linux/module.h>
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#include <linux/signal.h>
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#include <linux/sched.h>
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#include <linux/mm.h>
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#include <linux/swap.h>
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#include <linux/kernel.h>
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#include <linux/string.h>
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#include <linux/types.h>
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#include <linux/init.h>
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#include <linux/memblock.h>
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#include <linux/gfp.h>
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#include <asm/setup.h>
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#include <linux/uaccess.h>
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#include <asm/page.h>
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#include <asm/pgalloc.h>
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#include <asm/traps.h>
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#include <asm/machdep.h>
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#include <asm/io.h>
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#ifdef CONFIG_ATARI
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#include <asm/atari_stram.h>
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#endif
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#include <asm/sections.h>
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#include <asm/tlb.h>
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/*
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 * ZERO_PAGE is a special page that is used for zero-initialized
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 * data and COW.
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 */
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void *empty_zero_page;
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EXPORT_SYMBOL(empty_zero_page);
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#ifdef CONFIG_MMU
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int m68k_virt_to_node_shift;
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void __init m68k_setup_node(int node)
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{
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	node_set_online(node);
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}
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#else /* CONFIG_MMU */
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/*
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 * paging_init() continues the virtual memory environment setup which
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 * was begun by the code in arch/head.S.
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 * The parameters are pointers to where to stick the starting and ending
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 * addresses of available kernel virtual memory.
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 */
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void __init paging_init(void)
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{
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	/*
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	 * Make sure start_mem is page aligned, otherwise bootmem and
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	 * page_alloc get different views of the world.
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	 */
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	unsigned long end_mem = memory_end & PAGE_MASK;
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	unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0, };
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	high_memory = (void *) end_mem;
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	empty_zero_page = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
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	if (!empty_zero_page)
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		panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
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		      __func__, PAGE_SIZE, PAGE_SIZE);
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	max_zone_pfn[ZONE_DMA] = end_mem >> PAGE_SHIFT;
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	free_area_init(max_zone_pfn);
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}
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#endif /* CONFIG_MMU */
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void free_initmem(void)
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{
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#ifndef CONFIG_MMU_SUN3
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	free_initmem_default(-1);
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#endif /* CONFIG_MMU_SUN3 */
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}
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#if defined(CONFIG_MMU) && !defined(CONFIG_COLDFIRE)
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#define VECTORS	&vectors[0]
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#else
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#define VECTORS	_ramvec
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#endif
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static inline void init_pointer_tables(void)
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{
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#if defined(CONFIG_MMU) && !defined(CONFIG_SUN3) && !defined(CONFIG_COLDFIRE)
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	int i, j;
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	/* insert pointer tables allocated so far into the tablelist */
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	init_pointer_table(kernel_pg_dir, TABLE_PGD);
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	for (i = 0; i < PTRS_PER_PGD; i++) {
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		pud_t *pud = (pud_t *)&kernel_pg_dir[i];
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		pmd_t *pmd_dir;
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		if (!pud_present(*pud))
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			continue;
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		pmd_dir = (pmd_t *)pgd_page_vaddr(kernel_pg_dir[i]);
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		init_pointer_table(pmd_dir, TABLE_PMD);
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		for (j = 0; j < PTRS_PER_PMD; j++) {
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			pmd_t *pmd = &pmd_dir[j];
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			pte_t *pte_dir;
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			if (!pmd_present(*pmd))
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				continue;
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			pte_dir = (pte_t *)pmd_page_vaddr(*pmd);
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			init_pointer_table(pte_dir, TABLE_PTE);
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		}
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	}
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#endif
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}
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void __init mem_init(void)
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{
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	/* this will put all memory onto the freelists */
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	memblock_free_all();
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	init_pointer_tables();
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}
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