The change adds some infrastructure for managing tile pmd's more generally, using pte_pmd() and pmd_pte() methods to translate pmd values to and from ptes, since on TILEPro a pmd is really just a nested structure holding a pgd (aka pte). Several existing pmd methods are moved into this framework, and a whole raft of additional pmd accessors are defined that are used by the transparent hugepage framework. The tile PTE now has a "client2" bit. The bit is used to indicate a transparent huge page is in the process of being split into subpages. This change also fixes a generic bug where the return value of the generic pmdp_splitting_flush() was incorrect. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
		
			
				
	
	
		
			122 lines
		
	
	
	
		
			3.3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			122 lines
		
	
	
	
		
			3.3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 *  mm/pgtable-generic.c
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 *
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 *  Generic pgtable methods declared in asm-generic/pgtable.h
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 *
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 *  Copyright (C) 2010  Linus Torvalds
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 */
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#include <linux/pagemap.h>
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#include <asm/tlb.h>
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#include <asm-generic/pgtable.h>
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#ifndef __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
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/*
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 * Only sets the access flags (dirty, accessed, and
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 * writable). Furthermore, we know it always gets set to a "more
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 * permissive" setting, which allows most architectures to optimize
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 * this. We return whether the PTE actually changed, which in turn
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 * instructs the caller to do things like update__mmu_cache.  This
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 * used to be done in the caller, but sparc needs minor faults to
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 * force that call on sun4c so we changed this macro slightly
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 */
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int ptep_set_access_flags(struct vm_area_struct *vma,
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			  unsigned long address, pte_t *ptep,
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			  pte_t entry, int dirty)
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{
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	int changed = !pte_same(*ptep, entry);
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	if (changed) {
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		set_pte_at(vma->vm_mm, address, ptep, entry);
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		flush_tlb_page(vma, address);
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	}
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	return changed;
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}
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#endif
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#ifndef __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
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int pmdp_set_access_flags(struct vm_area_struct *vma,
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			  unsigned long address, pmd_t *pmdp,
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			  pmd_t entry, int dirty)
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{
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#ifdef CONFIG_TRANSPARENT_HUGEPAGE
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	int changed = !pmd_same(*pmdp, entry);
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	VM_BUG_ON(address & ~HPAGE_PMD_MASK);
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	if (changed) {
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		set_pmd_at(vma->vm_mm, address, pmdp, entry);
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		flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
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	}
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	return changed;
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#else /* CONFIG_TRANSPARENT_HUGEPAGE */
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	BUG();
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	return 0;
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#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
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}
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#endif
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#ifndef __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
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int ptep_clear_flush_young(struct vm_area_struct *vma,
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			   unsigned long address, pte_t *ptep)
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{
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	int young;
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	young = ptep_test_and_clear_young(vma, address, ptep);
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	if (young)
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		flush_tlb_page(vma, address);
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	return young;
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}
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#endif
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#ifndef __HAVE_ARCH_PMDP_CLEAR_YOUNG_FLUSH
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int pmdp_clear_flush_young(struct vm_area_struct *vma,
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			   unsigned long address, pmd_t *pmdp)
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{
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	int young;
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#ifdef CONFIG_TRANSPARENT_HUGEPAGE
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	VM_BUG_ON(address & ~HPAGE_PMD_MASK);
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#else
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	BUG();
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#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
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	young = pmdp_test_and_clear_young(vma, address, pmdp);
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	if (young)
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		flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
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	return young;
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}
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#endif
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#ifndef __HAVE_ARCH_PTEP_CLEAR_FLUSH
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pte_t ptep_clear_flush(struct vm_area_struct *vma, unsigned long address,
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		       pte_t *ptep)
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{
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	pte_t pte;
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	pte = ptep_get_and_clear((vma)->vm_mm, address, ptep);
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	flush_tlb_page(vma, address);
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	return pte;
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}
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#endif
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#ifndef __HAVE_ARCH_PMDP_CLEAR_FLUSH
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#ifdef CONFIG_TRANSPARENT_HUGEPAGE
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pmd_t pmdp_clear_flush(struct vm_area_struct *vma, unsigned long address,
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		       pmd_t *pmdp)
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{
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	pmd_t pmd;
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	VM_BUG_ON(address & ~HPAGE_PMD_MASK);
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	pmd = pmdp_get_and_clear(vma->vm_mm, address, pmdp);
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	flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
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	return pmd;
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}
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#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
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#endif
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#ifndef __HAVE_ARCH_PMDP_SPLITTING_FLUSH
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#ifdef CONFIG_TRANSPARENT_HUGEPAGE
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void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address,
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			  pmd_t *pmdp)
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{
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	pmd_t pmd = pmd_mksplitting(*pmdp);
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	VM_BUG_ON(address & ~HPAGE_PMD_MASK);
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	set_pmd_at(vma->vm_mm, address, pmdp, pmd);
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	/* tlb flush only to serialize against gup-fast */
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	flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
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}
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#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
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#endif
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