/* *  mm/pgtable-generic.c * *  Generic pgtable methods declared in asm-generic/pgtable.h * *  Copyright (C) 2010  Linus Torvalds */ #include <linux/pagemap.h>#include <asm/tlb.h>#include <asm-generic/pgtable.h> #ifndef __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS/* * Only sets the access flags (dirty, accessed, and * writable). Furthermore, we know it always gets set to a "more * permissive" setting, which allows most architectures to optimize * this. We return whether the PTE actually changed, which in turn * instructs the caller to do things like update__mmu_cache.  This * used to be done in the caller, but sparc needs minor faults to * force that call on sun4c so we changed this macro slightly */int ptep_set_access_flags(struct vm_area_struct *vma,			  unsigned long address, pte_t *ptep,			  pte_t entry, int dirty){	int changed = !pte_same(*ptep, entry);	if (changed) {		set_pte_at(vma->vm_mm, address, ptep, entry);		flush_tlb_page(vma, address);	}	return changed;}#endif #ifndef __HAVE_ARCH_PMDP_SET_ACCESS_FLAGSint pmdp_set_access_flags(struct vm_area_struct *vma,			  unsigned long address, pmd_t *pmdp,			  pmd_t entry, int dirty){#ifdef CONFIG_TRANSPARENT_HUGEPAGE	int changed = !pmd_same(*pmdp, entry);	VM_BUG_ON(address & ~HPAGE_PMD_MASK);	if (changed) {		set_pmd_at(vma->vm_mm, address, pmdp, entry);		flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);	}	return changed;#else /* CONFIG_TRANSPARENT_HUGEPAGE */	BUG();	return 0;#endif /* CONFIG_TRANSPARENT_HUGEPAGE */}#endif #ifndef __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSHint ptep_clear_flush_young(struct vm_area_struct *vma,			   unsigned long address, pte_t *ptep){	int young;	young = ptep_test_and_clear_young(vma, address, ptep);	if (young)		flush_tlb_page(vma, address);	return young;}#endif #ifndef __HAVE_ARCH_PMDP_CLEAR_YOUNG_FLUSHint pmdp_clear_flush_young(struct vm_area_struct *vma,			   unsigned long address, pmd_t *pmdp){	int young;#ifdef CONFIG_TRANSPARENT_HUGEPAGE	VM_BUG_ON(address & ~HPAGE_PMD_MASK);#else	BUG();#endif /* CONFIG_TRANSPARENT_HUGEPAGE */	young = pmdp_test_and_clear_young(vma, address, pmdp);	if (young)		flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);	return young;}#endif #ifndef __HAVE_ARCH_PTEP_CLEAR_FLUSHpte_t ptep_clear_flush(struct vm_area_struct *vma, unsigned long address,		       pte_t *ptep){	pte_t pte;	pte = ptep_get_and_clear((vma)->vm_mm, address, ptep);	flush_tlb_page(vma, address);	return pte;}#endif #ifndef __HAVE_ARCH_PMDP_CLEAR_FLUSH#ifdef CONFIG_TRANSPARENT_HUGEPAGEpmd_t pmdp_clear_flush(struct vm_area_struct *vma, unsigned long address,		       pmd_t *pmdp){	pmd_t pmd;	VM_BUG_ON(address & ~HPAGE_PMD_MASK);	pmd = pmdp_get_and_clear(vma->vm_mm, address, pmdp);	flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);	return pmd;}#endif /* CONFIG_TRANSPARENT_HUGEPAGE */#endif #ifndef __HAVE_ARCH_PMDP_SPLITTING_FLUSH#ifdef CONFIG_TRANSPARENT_HUGEPAGEvoid pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address,			  pmd_t *pmdp){	pmd_t pmd = pmd_mksplitting(*pmdp);	VM_BUG_ON(address & ~HPAGE_PMD_MASK);	set_pmd_at(vma->vm_mm, address, pmdp, pmd);	/* tlb flush only to serialize against gup-fast */	flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);}#endif /* CONFIG_TRANSPARENT_HUGEPAGE */#endif