754 lines
		
	
	
		
			22 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			754 lines
		
	
	
		
			22 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0-or-later */
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| /* include/asm-generic/tlb.h
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|  *
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|  *	Generic TLB shootdown code
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|  *
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|  * Copyright 2001 Red Hat, Inc.
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|  * Based on code from mm/memory.c Copyright Linus Torvalds and others.
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|  *
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|  * Copyright 2011 Red Hat, Inc., Peter Zijlstra
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|  */
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| #ifndef _ASM_GENERIC__TLB_H
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| #define _ASM_GENERIC__TLB_H
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| 
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| #include <linux/mmu_notifier.h>
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| #include <linux/swap.h>
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| #include <linux/hugetlb_inline.h>
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| #include <asm/tlbflush.h>
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| #include <asm/cacheflush.h>
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| 
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| /*
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|  * Blindly accessing user memory from NMI context can be dangerous
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|  * if we're in the middle of switching the current user task or switching
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|  * the loaded mm.
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|  */
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| #ifndef nmi_uaccess_okay
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| # define nmi_uaccess_okay() true
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| #endif
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| 
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| #ifdef CONFIG_MMU
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| 
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| /*
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|  * Generic MMU-gather implementation.
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|  *
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|  * The mmu_gather data structure is used by the mm code to implement the
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|  * correct and efficient ordering of freeing pages and TLB invalidations.
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|  *
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|  * This correct ordering is:
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|  *
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|  *  1) unhook page
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|  *  2) TLB invalidate page
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|  *  3) free page
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|  *
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|  * That is, we must never free a page before we have ensured there are no live
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|  * translations left to it. Otherwise it might be possible to observe (or
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|  * worse, change) the page content after it has been reused.
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|  *
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|  * The mmu_gather API consists of:
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|  *
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|  *  - tlb_gather_mmu() / tlb_gather_mmu_fullmm() / tlb_finish_mmu()
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|  *
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|  *    start and finish a mmu_gather
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|  *
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|  *    Finish in particular will issue a (final) TLB invalidate and free
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|  *    all (remaining) queued pages.
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|  *
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|  *  - tlb_start_vma() / tlb_end_vma(); marks the start / end of a VMA
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|  *
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|  *    Defaults to flushing at tlb_end_vma() to reset the range; helps when
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|  *    there's large holes between the VMAs.
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|  *
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|  *  - tlb_remove_table()
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|  *
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|  *    tlb_remove_table() is the basic primitive to free page-table directories
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|  *    (__p*_free_tlb()).  In it's most primitive form it is an alias for
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|  *    tlb_remove_page() below, for when page directories are pages and have no
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|  *    additional constraints.
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|  *
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|  *    See also MMU_GATHER_TABLE_FREE and MMU_GATHER_RCU_TABLE_FREE.
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|  *
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|  *  - tlb_remove_page() / __tlb_remove_page()
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|  *  - tlb_remove_page_size() / __tlb_remove_page_size()
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|  *  - __tlb_remove_folio_pages()
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|  *
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|  *    __tlb_remove_page_size() is the basic primitive that queues a page for
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|  *    freeing. __tlb_remove_page() assumes PAGE_SIZE. Both will return a
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|  *    boolean indicating if the queue is (now) full and a call to
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|  *    tlb_flush_mmu() is required.
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|  *
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|  *    tlb_remove_page() and tlb_remove_page_size() imply the call to
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|  *    tlb_flush_mmu() when required and has no return value.
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|  *
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|  *    __tlb_remove_folio_pages() is similar to __tlb_remove_page(), however,
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|  *    instead of removing a single page, remove the given number of consecutive
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|  *    pages that are all part of the same (large) folio: just like calling
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|  *    __tlb_remove_page() on each page individually.
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|  *
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|  *  - tlb_change_page_size()
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|  *
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|  *    call before __tlb_remove_page*() to set the current page-size; implies a
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|  *    possible tlb_flush_mmu() call.
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|  *
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|  *  - tlb_flush_mmu() / tlb_flush_mmu_tlbonly()
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|  *
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|  *    tlb_flush_mmu_tlbonly() - does the TLB invalidate (and resets
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|  *                              related state, like the range)
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|  *
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|  *    tlb_flush_mmu() - in addition to the above TLB invalidate, also frees
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|  *			whatever pages are still batched.
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|  *
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|  *  - mmu_gather::fullmm
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|  *
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|  *    A flag set by tlb_gather_mmu_fullmm() to indicate we're going to free
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|  *    the entire mm; this allows a number of optimizations.
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|  *
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|  *    - We can ignore tlb_{start,end}_vma(); because we don't
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|  *      care about ranges. Everything will be shot down.
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|  *
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|  *    - (RISC) architectures that use ASIDs can cycle to a new ASID
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|  *      and delay the invalidation until ASID space runs out.
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|  *
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|  *  - mmu_gather::need_flush_all
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|  *
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|  *    A flag that can be set by the arch code if it wants to force
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|  *    flush the entire TLB irrespective of the range. For instance
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|  *    x86-PAE needs this when changing top-level entries.
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|  *
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|  * And allows the architecture to provide and implement tlb_flush():
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|  *
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|  * tlb_flush() may, in addition to the above mentioned mmu_gather fields, make
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|  * use of:
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|  *
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|  *  - mmu_gather::start / mmu_gather::end
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|  *
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|  *    which provides the range that needs to be flushed to cover the pages to
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|  *    be freed.
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|  *
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|  *  - mmu_gather::freed_tables
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|  *
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|  *    set when we freed page table pages
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|  *
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|  *  - tlb_get_unmap_shift() / tlb_get_unmap_size()
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|  *
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|  *    returns the smallest TLB entry size unmapped in this range.
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|  *
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|  * If an architecture does not provide tlb_flush() a default implementation
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|  * based on flush_tlb_range() will be used, unless MMU_GATHER_NO_RANGE is
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|  * specified, in which case we'll default to flush_tlb_mm().
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|  *
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|  * Additionally there are a few opt-in features:
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|  *
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|  *  MMU_GATHER_PAGE_SIZE
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|  *
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|  *  This ensures we call tlb_flush() every time tlb_change_page_size() actually
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|  *  changes the size and provides mmu_gather::page_size to tlb_flush().
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|  *
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|  *  This might be useful if your architecture has size specific TLB
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|  *  invalidation instructions.
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|  *
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|  *  MMU_GATHER_TABLE_FREE
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|  *
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|  *  This provides tlb_remove_table(), to be used instead of tlb_remove_page()
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|  *  for page directores (__p*_free_tlb()).
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|  *
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|  *  Useful if your architecture has non-page page directories.
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|  *
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|  *  When used, an architecture is expected to provide __tlb_remove_table()
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|  *  which does the actual freeing of these pages.
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|  *
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|  *  MMU_GATHER_RCU_TABLE_FREE
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|  *
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|  *  Like MMU_GATHER_TABLE_FREE, and adds semi-RCU semantics to the free (see
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|  *  comment below).
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|  *
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|  *  Useful if your architecture doesn't use IPIs for remote TLB invalidates
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|  *  and therefore doesn't naturally serialize with software page-table walkers.
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|  *
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|  *  MMU_GATHER_NO_FLUSH_CACHE
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|  *
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|  *  Indicates the architecture has flush_cache_range() but it needs *NOT* be called
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|  *  before unmapping a VMA.
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|  *
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|  *  NOTE: strictly speaking we shouldn't have this knob and instead rely on
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|  *	  flush_cache_range() being a NOP, except Sparc64 seems to be
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|  *	  different here.
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|  *
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|  *  MMU_GATHER_MERGE_VMAS
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|  *
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|  *  Indicates the architecture wants to merge ranges over VMAs; typical when
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|  *  multiple range invalidates are more expensive than a full invalidate.
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|  *
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|  *  MMU_GATHER_NO_RANGE
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|  *
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|  *  Use this if your architecture lacks an efficient flush_tlb_range(). This
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|  *  option implies MMU_GATHER_MERGE_VMAS above.
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|  *
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|  *  MMU_GATHER_NO_GATHER
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|  *
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|  *  If the option is set the mmu_gather will not track individual pages for
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|  *  delayed page free anymore. A platform that enables the option needs to
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|  *  provide its own implementation of the __tlb_remove_page_size() function to
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|  *  free pages.
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|  *
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|  *  This is useful if your architecture already flushes TLB entries in the
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|  *  various ptep_get_and_clear() functions.
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|  */
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| 
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| #ifdef CONFIG_MMU_GATHER_TABLE_FREE
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| 
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| struct mmu_table_batch {
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| #ifdef CONFIG_MMU_GATHER_RCU_TABLE_FREE
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| 	struct rcu_head		rcu;
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| #endif
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| 	unsigned int		nr;
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| 	void			*tables[];
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| };
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| 
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| #define MAX_TABLE_BATCH		\
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| 	((PAGE_SIZE - sizeof(struct mmu_table_batch)) / sizeof(void *))
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| 
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| extern void tlb_remove_table(struct mmu_gather *tlb, void *table);
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| 
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| #else /* !CONFIG_MMU_GATHER_HAVE_TABLE_FREE */
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| 
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| /*
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|  * Without MMU_GATHER_TABLE_FREE the architecture is assumed to have page based
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|  * page directories and we can use the normal page batching to free them.
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|  */
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| #define tlb_remove_table(tlb, page) tlb_remove_page((tlb), (page))
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| 
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| #endif /* CONFIG_MMU_GATHER_TABLE_FREE */
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| 
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| #ifdef CONFIG_MMU_GATHER_RCU_TABLE_FREE
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| /*
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|  * This allows an architecture that does not use the linux page-tables for
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|  * hardware to skip the TLBI when freeing page tables.
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|  */
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| #ifndef tlb_needs_table_invalidate
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| #define tlb_needs_table_invalidate() (true)
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| #endif
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| 
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| void tlb_remove_table_sync_one(void);
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| 
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| #else
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| 
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| #ifdef tlb_needs_table_invalidate
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| #error tlb_needs_table_invalidate() requires MMU_GATHER_RCU_TABLE_FREE
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| #endif
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| 
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| static inline void tlb_remove_table_sync_one(void) { }
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| 
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| #endif /* CONFIG_MMU_GATHER_RCU_TABLE_FREE */
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| 
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| 
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| #ifndef CONFIG_MMU_GATHER_NO_GATHER
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| /*
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|  * If we can't allocate a page to make a big batch of page pointers
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|  * to work on, then just handle a few from the on-stack structure.
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|  */
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| #define MMU_GATHER_BUNDLE	8
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| 
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| struct mmu_gather_batch {
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| 	struct mmu_gather_batch	*next;
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| 	unsigned int		nr;
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| 	unsigned int		max;
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| 	struct encoded_page	*encoded_pages[];
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| };
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| 
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| #define MAX_GATHER_BATCH	\
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| 	((PAGE_SIZE - sizeof(struct mmu_gather_batch)) / sizeof(void *))
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| 
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| /*
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|  * Limit the maximum number of mmu_gather batches to reduce a risk of soft
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|  * lockups for non-preemptible kernels on huge machines when a lot of memory
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|  * is zapped during unmapping.
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|  * 10K pages freed at once should be safe even without a preemption point.
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|  */
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| #define MAX_GATHER_BATCH_COUNT	(10000UL/MAX_GATHER_BATCH)
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| 
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| extern bool __tlb_remove_page_size(struct mmu_gather *tlb, struct page *page,
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| 		bool delay_rmap, int page_size);
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| bool __tlb_remove_folio_pages(struct mmu_gather *tlb, struct page *page,
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| 		unsigned int nr_pages, bool delay_rmap);
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| 
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| #ifdef CONFIG_SMP
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| /*
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|  * This both sets 'delayed_rmap', and returns true. It would be an inline
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|  * function, except we define it before the 'struct mmu_gather'.
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|  */
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| #define tlb_delay_rmap(tlb) (((tlb)->delayed_rmap = 1), true)
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| extern void tlb_flush_rmaps(struct mmu_gather *tlb, struct vm_area_struct *vma);
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| #endif
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| 
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| #endif
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| 
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| /*
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|  * We have a no-op version of the rmap removal that doesn't
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|  * delay anything. That is used on S390, which flushes remote
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|  * TLBs synchronously, and on UP, which doesn't have any
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|  * remote TLBs to flush and is not preemptible due to this
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|  * all happening under the page table lock.
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|  */
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| #ifndef tlb_delay_rmap
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| #define tlb_delay_rmap(tlb) (false)
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| static inline void tlb_flush_rmaps(struct mmu_gather *tlb, struct vm_area_struct *vma) { }
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| #endif
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| 
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| /*
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|  * struct mmu_gather is an opaque type used by the mm code for passing around
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|  * any data needed by arch specific code for tlb_remove_page.
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|  */
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| struct mmu_gather {
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| 	struct mm_struct	*mm;
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| 
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| #ifdef CONFIG_MMU_GATHER_TABLE_FREE
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| 	struct mmu_table_batch	*batch;
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| #endif
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| 
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| 	unsigned long		start;
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| 	unsigned long		end;
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| 	/*
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| 	 * we are in the middle of an operation to clear
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| 	 * a full mm and can make some optimizations
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| 	 */
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| 	unsigned int		fullmm : 1;
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| 
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| 	/*
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| 	 * we have performed an operation which
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| 	 * requires a complete flush of the tlb
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| 	 */
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| 	unsigned int		need_flush_all : 1;
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| 
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| 	/*
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| 	 * we have removed page directories
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| 	 */
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| 	unsigned int		freed_tables : 1;
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| 
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| 	/*
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| 	 * Do we have pending delayed rmap removals?
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| 	 */
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| 	unsigned int		delayed_rmap : 1;
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| 
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| 	/*
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| 	 * at which levels have we cleared entries?
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| 	 */
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| 	unsigned int		cleared_ptes : 1;
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| 	unsigned int		cleared_pmds : 1;
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| 	unsigned int		cleared_puds : 1;
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| 	unsigned int		cleared_p4ds : 1;
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| 
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| 	/*
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| 	 * tracks VM_EXEC | VM_HUGETLB in tlb_start_vma
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| 	 */
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| 	unsigned int		vma_exec : 1;
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| 	unsigned int		vma_huge : 1;
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| 	unsigned int		vma_pfn  : 1;
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| 
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| 	unsigned int		batch_count;
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| 
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| #ifndef CONFIG_MMU_GATHER_NO_GATHER
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| 	struct mmu_gather_batch *active;
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| 	struct mmu_gather_batch	local;
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| 	struct page		*__pages[MMU_GATHER_BUNDLE];
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| 
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| #ifdef CONFIG_MMU_GATHER_PAGE_SIZE
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| 	unsigned int page_size;
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| #endif
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| #endif
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| };
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| 
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| void tlb_flush_mmu(struct mmu_gather *tlb);
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| 
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| static inline void __tlb_adjust_range(struct mmu_gather *tlb,
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| 				      unsigned long address,
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| 				      unsigned int range_size)
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| {
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| 	tlb->start = min(tlb->start, address);
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| 	tlb->end = max(tlb->end, address + range_size);
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| }
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| 
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| static inline void __tlb_reset_range(struct mmu_gather *tlb)
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| {
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| 	if (tlb->fullmm) {
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| 		tlb->start = tlb->end = ~0;
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| 	} else {
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| 		tlb->start = TASK_SIZE;
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| 		tlb->end = 0;
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| 	}
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| 	tlb->freed_tables = 0;
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| 	tlb->cleared_ptes = 0;
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| 	tlb->cleared_pmds = 0;
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| 	tlb->cleared_puds = 0;
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| 	tlb->cleared_p4ds = 0;
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| 	/*
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| 	 * Do not reset mmu_gather::vma_* fields here, we do not
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| 	 * call into tlb_start_vma() again to set them if there is an
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| 	 * intermediate flush.
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| 	 */
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| }
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| 
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| #ifdef CONFIG_MMU_GATHER_NO_RANGE
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| 
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| #if defined(tlb_flush)
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| #error MMU_GATHER_NO_RANGE relies on default tlb_flush()
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| #endif
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| 
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| /*
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|  * When an architecture does not have efficient means of range flushing TLBs
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|  * there is no point in doing intermediate flushes on tlb_end_vma() to keep the
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|  * range small. We equally don't have to worry about page granularity or other
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|  * things.
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|  *
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|  * All we need to do is issue a full flush for any !0 range.
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|  */
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| static inline void tlb_flush(struct mmu_gather *tlb)
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| {
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| 	if (tlb->end)
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| 		flush_tlb_mm(tlb->mm);
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| }
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| 
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| #else /* CONFIG_MMU_GATHER_NO_RANGE */
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| 
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| #ifndef tlb_flush
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| /*
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|  * When an architecture does not provide its own tlb_flush() implementation
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|  * but does have a reasonably efficient flush_vma_range() implementation
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|  * use that.
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|  */
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| static inline void tlb_flush(struct mmu_gather *tlb)
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| {
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| 	if (tlb->fullmm || tlb->need_flush_all) {
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| 		flush_tlb_mm(tlb->mm);
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| 	} else if (tlb->end) {
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| 		struct vm_area_struct vma = {
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| 			.vm_mm = tlb->mm,
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| 			.vm_flags = (tlb->vma_exec ? VM_EXEC    : 0) |
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| 				    (tlb->vma_huge ? VM_HUGETLB : 0),
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| 		};
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| 
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| 		flush_tlb_range(&vma, tlb->start, tlb->end);
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| 	}
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| }
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| #endif
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| 
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| #endif /* CONFIG_MMU_GATHER_NO_RANGE */
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| 
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| static inline void
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| tlb_update_vma_flags(struct mmu_gather *tlb, struct vm_area_struct *vma)
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| {
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| 	/*
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| 	 * flush_tlb_range() implementations that look at VM_HUGETLB (tile,
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| 	 * mips-4k) flush only large pages.
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| 	 *
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| 	 * flush_tlb_range() implementations that flush I-TLB also flush D-TLB
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| 	 * (tile, xtensa, arm), so it's ok to just add VM_EXEC to an existing
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| 	 * range.
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| 	 *
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| 	 * We rely on tlb_end_vma() to issue a flush, such that when we reset
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| 	 * these values the batch is empty.
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| 	 */
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| 	tlb->vma_huge = is_vm_hugetlb_page(vma);
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| 	tlb->vma_exec = !!(vma->vm_flags & VM_EXEC);
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| 	tlb->vma_pfn  = !!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP));
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| }
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| 
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| static inline void tlb_flush_mmu_tlbonly(struct mmu_gather *tlb)
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| {
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| 	/*
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| 	 * Anything calling __tlb_adjust_range() also sets at least one of
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| 	 * these bits.
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| 	 */
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| 	if (!(tlb->freed_tables || tlb->cleared_ptes || tlb->cleared_pmds ||
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| 	      tlb->cleared_puds || tlb->cleared_p4ds))
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| 		return;
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| 
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| 	tlb_flush(tlb);
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| 	__tlb_reset_range(tlb);
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| }
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| 
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| static inline void tlb_remove_page_size(struct mmu_gather *tlb,
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| 					struct page *page, int page_size)
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| {
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| 	if (__tlb_remove_page_size(tlb, page, false, page_size))
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| 		tlb_flush_mmu(tlb);
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| }
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| 
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| static __always_inline bool __tlb_remove_page(struct mmu_gather *tlb,
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| 		struct page *page, bool delay_rmap)
 | |
| {
 | |
| 	return __tlb_remove_page_size(tlb, page, delay_rmap, PAGE_SIZE);
 | |
| }
 | |
| 
 | |
| /* tlb_remove_page
 | |
|  *	Similar to __tlb_remove_page but will call tlb_flush_mmu() itself when
 | |
|  *	required.
 | |
|  */
 | |
| static inline void tlb_remove_page(struct mmu_gather *tlb, struct page *page)
 | |
| {
 | |
| 	return tlb_remove_page_size(tlb, page, PAGE_SIZE);
 | |
| }
 | |
| 
 | |
| static inline void tlb_remove_ptdesc(struct mmu_gather *tlb, void *pt)
 | |
| {
 | |
| 	tlb_remove_table(tlb, pt);
 | |
| }
 | |
| 
 | |
| /* Like tlb_remove_ptdesc, but for page-like page directories. */
 | |
| static inline void tlb_remove_page_ptdesc(struct mmu_gather *tlb, struct ptdesc *pt)
 | |
| {
 | |
| 	tlb_remove_page(tlb, ptdesc_page(pt));
 | |
| }
 | |
| 
 | |
| static inline void tlb_change_page_size(struct mmu_gather *tlb,
 | |
| 						     unsigned int page_size)
 | |
| {
 | |
| #ifdef CONFIG_MMU_GATHER_PAGE_SIZE
 | |
| 	if (tlb->page_size && tlb->page_size != page_size) {
 | |
| 		if (!tlb->fullmm && !tlb->need_flush_all)
 | |
| 			tlb_flush_mmu(tlb);
 | |
| 	}
 | |
| 
 | |
| 	tlb->page_size = page_size;
 | |
| #endif
 | |
| }
 | |
| 
 | |
| static inline unsigned long tlb_get_unmap_shift(struct mmu_gather *tlb)
 | |
| {
 | |
| 	if (tlb->cleared_ptes)
 | |
| 		return PAGE_SHIFT;
 | |
| 	if (tlb->cleared_pmds)
 | |
| 		return PMD_SHIFT;
 | |
| 	if (tlb->cleared_puds)
 | |
| 		return PUD_SHIFT;
 | |
| 	if (tlb->cleared_p4ds)
 | |
| 		return P4D_SHIFT;
 | |
| 
 | |
| 	return PAGE_SHIFT;
 | |
| }
 | |
| 
 | |
| static inline unsigned long tlb_get_unmap_size(struct mmu_gather *tlb)
 | |
| {
 | |
| 	return 1UL << tlb_get_unmap_shift(tlb);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * In the case of tlb vma handling, we can optimise these away in the
 | |
|  * case where we're doing a full MM flush.  When we're doing a munmap,
 | |
|  * the vmas are adjusted to only cover the region to be torn down.
 | |
|  */
 | |
| static inline void tlb_start_vma(struct mmu_gather *tlb, struct vm_area_struct *vma)
 | |
| {
 | |
| 	if (tlb->fullmm)
 | |
| 		return;
 | |
| 
 | |
| 	tlb_update_vma_flags(tlb, vma);
 | |
| #ifndef CONFIG_MMU_GATHER_NO_FLUSH_CACHE
 | |
| 	flush_cache_range(vma, vma->vm_start, vma->vm_end);
 | |
| #endif
 | |
| }
 | |
| 
 | |
| static inline void tlb_end_vma(struct mmu_gather *tlb, struct vm_area_struct *vma)
 | |
| {
 | |
| 	if (tlb->fullmm)
 | |
| 		return;
 | |
| 
 | |
| 	/*
 | |
| 	 * VM_PFNMAP is more fragile because the core mm will not track the
 | |
| 	 * page mapcount -- there might not be page-frames for these PFNs after
 | |
| 	 * all. Force flush TLBs for such ranges to avoid munmap() vs
 | |
| 	 * unmap_mapping_range() races.
 | |
| 	 */
 | |
| 	if (tlb->vma_pfn || !IS_ENABLED(CONFIG_MMU_GATHER_MERGE_VMAS)) {
 | |
| 		/*
 | |
| 		 * Do a TLB flush and reset the range at VMA boundaries; this avoids
 | |
| 		 * the ranges growing with the unused space between consecutive VMAs.
 | |
| 		 */
 | |
| 		tlb_flush_mmu_tlbonly(tlb);
 | |
| 	}
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * tlb_flush_{pte|pmd|pud|p4d}_range() adjust the tlb->start and tlb->end,
 | |
|  * and set corresponding cleared_*.
 | |
|  */
 | |
| static inline void tlb_flush_pte_range(struct mmu_gather *tlb,
 | |
| 				     unsigned long address, unsigned long size)
 | |
| {
 | |
| 	__tlb_adjust_range(tlb, address, size);
 | |
| 	tlb->cleared_ptes = 1;
 | |
| }
 | |
| 
 | |
| static inline void tlb_flush_pmd_range(struct mmu_gather *tlb,
 | |
| 				     unsigned long address, unsigned long size)
 | |
| {
 | |
| 	__tlb_adjust_range(tlb, address, size);
 | |
| 	tlb->cleared_pmds = 1;
 | |
| }
 | |
| 
 | |
| static inline void tlb_flush_pud_range(struct mmu_gather *tlb,
 | |
| 				     unsigned long address, unsigned long size)
 | |
| {
 | |
| 	__tlb_adjust_range(tlb, address, size);
 | |
| 	tlb->cleared_puds = 1;
 | |
| }
 | |
| 
 | |
| static inline void tlb_flush_p4d_range(struct mmu_gather *tlb,
 | |
| 				     unsigned long address, unsigned long size)
 | |
| {
 | |
| 	__tlb_adjust_range(tlb, address, size);
 | |
| 	tlb->cleared_p4ds = 1;
 | |
| }
 | |
| 
 | |
| #ifndef __tlb_remove_tlb_entry
 | |
| static inline void __tlb_remove_tlb_entry(struct mmu_gather *tlb, pte_t *ptep, unsigned long address)
 | |
| {
 | |
| }
 | |
| #endif
 | |
| 
 | |
| /**
 | |
|  * tlb_remove_tlb_entry - remember a pte unmapping for later tlb invalidation.
 | |
|  *
 | |
|  * Record the fact that pte's were really unmapped by updating the range,
 | |
|  * so we can later optimise away the tlb invalidate.   This helps when
 | |
|  * userspace is unmapping already-unmapped pages, which happens quite a lot.
 | |
|  */
 | |
| #define tlb_remove_tlb_entry(tlb, ptep, address)		\
 | |
| 	do {							\
 | |
| 		tlb_flush_pte_range(tlb, address, PAGE_SIZE);	\
 | |
| 		__tlb_remove_tlb_entry(tlb, ptep, address);	\
 | |
| 	} while (0)
 | |
| 
 | |
| /**
 | |
|  * tlb_remove_tlb_entries - remember unmapping of multiple consecutive ptes for
 | |
|  *			    later tlb invalidation.
 | |
|  *
 | |
|  * Similar to tlb_remove_tlb_entry(), but remember unmapping of multiple
 | |
|  * consecutive ptes instead of only a single one.
 | |
|  */
 | |
| static inline void tlb_remove_tlb_entries(struct mmu_gather *tlb,
 | |
| 		pte_t *ptep, unsigned int nr, unsigned long address)
 | |
| {
 | |
| 	tlb_flush_pte_range(tlb, address, PAGE_SIZE * nr);
 | |
| 	for (;;) {
 | |
| 		__tlb_remove_tlb_entry(tlb, ptep, address);
 | |
| 		if (--nr == 0)
 | |
| 			break;
 | |
| 		ptep++;
 | |
| 		address += PAGE_SIZE;
 | |
| 	}
 | |
| }
 | |
| 
 | |
| #define tlb_remove_huge_tlb_entry(h, tlb, ptep, address)	\
 | |
| 	do {							\
 | |
| 		unsigned long _sz = huge_page_size(h);		\
 | |
| 		if (_sz >= P4D_SIZE)				\
 | |
| 			tlb_flush_p4d_range(tlb, address, _sz);	\
 | |
| 		else if (_sz >= PUD_SIZE)			\
 | |
| 			tlb_flush_pud_range(tlb, address, _sz);	\
 | |
| 		else if (_sz >= PMD_SIZE)			\
 | |
| 			tlb_flush_pmd_range(tlb, address, _sz);	\
 | |
| 		else						\
 | |
| 			tlb_flush_pte_range(tlb, address, _sz);	\
 | |
| 		__tlb_remove_tlb_entry(tlb, ptep, address);	\
 | |
| 	} while (0)
 | |
| 
 | |
| /**
 | |
|  * tlb_remove_pmd_tlb_entry - remember a pmd mapping for later tlb invalidation
 | |
|  * This is a nop so far, because only x86 needs it.
 | |
|  */
 | |
| #ifndef __tlb_remove_pmd_tlb_entry
 | |
| #define __tlb_remove_pmd_tlb_entry(tlb, pmdp, address) do {} while (0)
 | |
| #endif
 | |
| 
 | |
| #define tlb_remove_pmd_tlb_entry(tlb, pmdp, address)			\
 | |
| 	do {								\
 | |
| 		tlb_flush_pmd_range(tlb, address, HPAGE_PMD_SIZE);	\
 | |
| 		__tlb_remove_pmd_tlb_entry(tlb, pmdp, address);		\
 | |
| 	} while (0)
 | |
| 
 | |
| /**
 | |
|  * tlb_remove_pud_tlb_entry - remember a pud mapping for later tlb
 | |
|  * invalidation. This is a nop so far, because only x86 needs it.
 | |
|  */
 | |
| #ifndef __tlb_remove_pud_tlb_entry
 | |
| #define __tlb_remove_pud_tlb_entry(tlb, pudp, address) do {} while (0)
 | |
| #endif
 | |
| 
 | |
| #define tlb_remove_pud_tlb_entry(tlb, pudp, address)			\
 | |
| 	do {								\
 | |
| 		tlb_flush_pud_range(tlb, address, HPAGE_PUD_SIZE);	\
 | |
| 		__tlb_remove_pud_tlb_entry(tlb, pudp, address);		\
 | |
| 	} while (0)
 | |
| 
 | |
| /*
 | |
|  * For things like page tables caches (ie caching addresses "inside" the
 | |
|  * page tables, like x86 does), for legacy reasons, flushing an
 | |
|  * individual page had better flush the page table caches behind it. This
 | |
|  * is definitely how x86 works, for example. And if you have an
 | |
|  * architected non-legacy page table cache (which I'm not aware of
 | |
|  * anybody actually doing), you're going to have some architecturally
 | |
|  * explicit flushing for that, likely *separate* from a regular TLB entry
 | |
|  * flush, and thus you'd need more than just some range expansion..
 | |
|  *
 | |
|  * So if we ever find an architecture
 | |
|  * that would want something that odd, I think it is up to that
 | |
|  * architecture to do its own odd thing, not cause pain for others
 | |
|  * http://lkml.kernel.org/r/CA+55aFzBggoXtNXQeng5d_mRoDnaMBE5Y+URs+PHR67nUpMtaw@mail.gmail.com
 | |
|  *
 | |
|  * For now w.r.t page table cache, mark the range_size as PAGE_SIZE
 | |
|  */
 | |
| 
 | |
| #ifndef pte_free_tlb
 | |
| #define pte_free_tlb(tlb, ptep, address)			\
 | |
| 	do {							\
 | |
| 		tlb_flush_pmd_range(tlb, address, PAGE_SIZE);	\
 | |
| 		tlb->freed_tables = 1;				\
 | |
| 		__pte_free_tlb(tlb, ptep, address);		\
 | |
| 	} while (0)
 | |
| #endif
 | |
| 
 | |
| #ifndef pmd_free_tlb
 | |
| #define pmd_free_tlb(tlb, pmdp, address)			\
 | |
| 	do {							\
 | |
| 		tlb_flush_pud_range(tlb, address, PAGE_SIZE);	\
 | |
| 		tlb->freed_tables = 1;				\
 | |
| 		__pmd_free_tlb(tlb, pmdp, address);		\
 | |
| 	} while (0)
 | |
| #endif
 | |
| 
 | |
| #ifndef pud_free_tlb
 | |
| #define pud_free_tlb(tlb, pudp, address)			\
 | |
| 	do {							\
 | |
| 		tlb_flush_p4d_range(tlb, address, PAGE_SIZE);	\
 | |
| 		tlb->freed_tables = 1;				\
 | |
| 		__pud_free_tlb(tlb, pudp, address);		\
 | |
| 	} while (0)
 | |
| #endif
 | |
| 
 | |
| #ifndef p4d_free_tlb
 | |
| #define p4d_free_tlb(tlb, pudp, address)			\
 | |
| 	do {							\
 | |
| 		__tlb_adjust_range(tlb, address, PAGE_SIZE);	\
 | |
| 		tlb->freed_tables = 1;				\
 | |
| 		__p4d_free_tlb(tlb, pudp, address);		\
 | |
| 	} while (0)
 | |
| #endif
 | |
| 
 | |
| #ifndef pte_needs_flush
 | |
| static inline bool pte_needs_flush(pte_t oldpte, pte_t newpte)
 | |
| {
 | |
| 	return true;
 | |
| }
 | |
| #endif
 | |
| 
 | |
| #ifndef huge_pmd_needs_flush
 | |
| static inline bool huge_pmd_needs_flush(pmd_t oldpmd, pmd_t newpmd)
 | |
| {
 | |
| 	return true;
 | |
| }
 | |
| #endif
 | |
| 
 | |
| #endif /* CONFIG_MMU */
 | |
| 
 | |
| #endif /* _ASM_GENERIC__TLB_H */
 |