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	Patch series "hugetlb: Disable huge pmd unshare for uffd-wp", v4. This series tries to disable huge pmd unshare of hugetlbfs backed memory for uffd-wp. Although uffd-wp of hugetlbfs is still during rfc stage, the idea of this series may be needed for multiple tasks (Axel's uffd minor fault series, and Mike's soft dirty series), so I picked it out from the larger series. This patch (of 4): It is a preparation work to be able to behave differently in the per architecture huge_pte_alloc() according to different VMA attributes. Pass it deeper into huge_pmd_share() so that we can avoid the find_vma() call. [peterx@redhat.com: build fix] Link: https://lkml.kernel.org/r/20210304164653.GB397383@xz-x1Link: https://lkml.kernel.org/r/20210218230633.15028-1-peterx@redhat.com Link: https://lkml.kernel.org/r/20210218230633.15028-2-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Suggested-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Adam Ruprecht <ruprecht@google.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Cannon Matthews <cannonmatthews@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chinwen Chang <chinwen.chang@mediatek.com> Cc: David Rientjes <rientjes@google.com> Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com> Cc: Huang Ying <ying.huang@intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Lokesh Gidra <lokeshgidra@google.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Michal Koutn" <mkoutny@suse.com> Cc: Michel Lespinasse <walken@google.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Mina Almasry <almasrymina@google.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Oliver Upton <oupton@google.com> Cc: Shaohua Li <shli@fb.com> Cc: Shawn Anastasio <shawn@anastas.io> Cc: Steven Price <steven.price@arm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
		
			
				
	
	
		
			69 lines
		
	
	
	
		
			1.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			69 lines
		
	
	
	
		
			1.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * MIPS Huge TLB Page Support for Kernel.
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 *
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 * This file is subject to the terms and conditions of the GNU General Public
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 * License.  See the file "COPYING" in the main directory of this archive
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 * for more details.
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 *
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 * Copyright (C) 2002, Rohit Seth <rohit.seth@intel.com>
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 * Copyright 2005, Embedded Alley Solutions, Inc.
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 * Matt Porter <mporter@embeddedalley.com>
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 * Copyright (C) 2008, 2009 Cavium Networks, Inc.
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 */
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#include <linux/fs.h>
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#include <linux/mm.h>
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#include <linux/hugetlb.h>
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#include <linux/pagemap.h>
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#include <linux/err.h>
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#include <linux/sysctl.h>
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#include <asm/mman.h>
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#include <asm/tlb.h>
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#include <asm/tlbflush.h>
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pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
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		      unsigned long addr, unsigned long sz)
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{
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	pgd_t *pgd;
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	p4d_t *p4d;
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	pud_t *pud;
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	pte_t *pte = NULL;
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	pgd = pgd_offset(mm, addr);
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	p4d = p4d_alloc(mm, pgd, addr);
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	pud = pud_alloc(mm, p4d, addr);
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	if (pud)
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		pte = (pte_t *)pmd_alloc(mm, pud, addr);
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	return pte;
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}
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pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr,
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		       unsigned long sz)
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{
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	pgd_t *pgd;
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	p4d_t *p4d;
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	pud_t *pud;
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	pmd_t *pmd = NULL;
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	pgd = pgd_offset(mm, addr);
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	if (pgd_present(*pgd)) {
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		p4d = p4d_offset(pgd, addr);
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		if (p4d_present(*p4d)) {
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			pud = pud_offset(p4d, addr);
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			if (pud_present(*pud))
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				pmd = pmd_offset(pud, addr);
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		}
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	}
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	return (pte_t *) pmd;
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}
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int pmd_huge(pmd_t pmd)
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{
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	return (pmd_val(pmd) & _PAGE_HUGE) != 0;
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}
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int pud_huge(pud_t pud)
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{
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	return (pud_val(pud) & _PAGE_HUGE) != 0;
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}
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