At the moment xtensa uses slab allocator for PTE table. It doesn't work with enabled split page table lock: slab uses page->slab_cache and page->first_page for its pages. These fields share stroage with page->ptl. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Chris Zankel <chris@zankel.net> Acked-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
		
			
				
	
	
		
			52 lines
		
	
	
	
		
			1.3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			52 lines
		
	
	
	
		
			1.3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * xtensa mmu stuff
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 *
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 * Extracted from init.c
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 */
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#include <linux/percpu.h>
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#include <linux/init.h>
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#include <linux/string.h>
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#include <linux/slab.h>
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#include <linux/cache.h>
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#include <asm/tlb.h>
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#include <asm/tlbflush.h>
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#include <asm/mmu_context.h>
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#include <asm/page.h>
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void __init paging_init(void)
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{
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	memset(swapper_pg_dir, 0, PAGE_SIZE);
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}
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/*
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 * Flush the mmu and reset associated register to default values.
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 */
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void __init init_mmu(void)
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{
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#if !(XCHAL_HAVE_PTP_MMU && XCHAL_HAVE_SPANNING_WAY)
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	/*
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	 * Writing zeros to the instruction and data TLBCFG special
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	 * registers ensure that valid values exist in the register.
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	 *
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	 * For existing PGSZID<w> fields, zero selects the first element
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	 * of the page-size array.  For nonexistent PGSZID<w> fields,
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	 * zero is the best value to write.  Also, when changing PGSZID<w>
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	 * fields, the corresponding TLB must be flushed.
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	 */
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	set_itlbcfg_register(0);
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	set_dtlbcfg_register(0);
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#endif
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	flush_tlb_all();
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	/* Set rasid register to a known value. */
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	set_rasid_register(ASID_INSERT(ASID_USER_FIRST));
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	/* Set PTEVADDR special register to the start of the page
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	 * table, which is in kernel mappable space (ie. not
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	 * statically mapped).  This register's value is undefined on
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	 * reset.
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	 */
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	set_ptevaddr_register(PGTABLE_START);
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}
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