|  | /* SPDX-License-Identifier: GPL-2.0-or-later */ | 
|  | /* include/asm-generic/tlb.h | 
|  | * | 
|  | *	Generic TLB shootdown code | 
|  | * | 
|  | * Copyright 2001 Red Hat, Inc. | 
|  | * Based on code from mm/memory.c Copyright Linus Torvalds and others. | 
|  | * | 
|  | * Copyright 2011 Red Hat, Inc., Peter Zijlstra | 
|  | */ | 
|  | #ifndef _ASM_GENERIC__TLB_H | 
|  | #define _ASM_GENERIC__TLB_H | 
|  |  | 
|  | #include <linux/mmu_notifier.h> | 
|  | #include <linux/swap.h> | 
|  | #include <linux/hugetlb_inline.h> | 
|  | #include <asm/tlbflush.h> | 
|  | #include <asm/cacheflush.h> | 
|  |  | 
|  | /* | 
|  | * Blindly accessing user memory from NMI context can be dangerous | 
|  | * if we're in the middle of switching the current user task or switching | 
|  | * the loaded mm. | 
|  | */ | 
|  | #ifndef nmi_uaccess_okay | 
|  | # define nmi_uaccess_okay() true | 
|  | #endif | 
|  |  | 
|  | #ifdef CONFIG_MMU | 
|  |  | 
|  | /* | 
|  | * Generic MMU-gather implementation. | 
|  | * | 
|  | * The mmu_gather data structure is used by the mm code to implement the | 
|  | * correct and efficient ordering of freeing pages and TLB invalidations. | 
|  | * | 
|  | * This correct ordering is: | 
|  | * | 
|  | *  1) unhook page | 
|  | *  2) TLB invalidate page | 
|  | *  3) free page | 
|  | * | 
|  | * That is, we must never free a page before we have ensured there are no live | 
|  | * translations left to it. Otherwise it might be possible to observe (or | 
|  | * worse, change) the page content after it has been reused. | 
|  | * | 
|  | * The mmu_gather API consists of: | 
|  | * | 
|  | *  - tlb_gather_mmu() / tlb_gather_mmu_fullmm() / tlb_finish_mmu() | 
|  | * | 
|  | *    start and finish a mmu_gather | 
|  | * | 
|  | *    Finish in particular will issue a (final) TLB invalidate and free | 
|  | *    all (remaining) queued pages. | 
|  | * | 
|  | *  - tlb_start_vma() / tlb_end_vma(); marks the start / end of a VMA | 
|  | * | 
|  | *    Defaults to flushing at tlb_end_vma() to reset the range; helps when | 
|  | *    there's large holes between the VMAs. | 
|  | * | 
|  | *  - tlb_remove_table() | 
|  | * | 
|  | *    tlb_remove_table() is the basic primitive to free page-table directories | 
|  | *    (__p*_free_tlb()).  In it's most primitive form it is an alias for | 
|  | *    tlb_remove_page() below, for when page directories are pages and have no | 
|  | *    additional constraints. | 
|  | * | 
|  | *    See also MMU_GATHER_TABLE_FREE and MMU_GATHER_RCU_TABLE_FREE. | 
|  | * | 
|  | *  - tlb_remove_page() / tlb_remove_page_size() | 
|  | *  - __tlb_remove_folio_pages() / __tlb_remove_page_size() | 
|  | *  - __tlb_remove_folio_pages_size() | 
|  | * | 
|  | *    __tlb_remove_folio_pages_size() is the basic primitive that queues pages | 
|  | *    for freeing. It will return a boolean indicating if the queue is (now) | 
|  | *    full and a call to tlb_flush_mmu() is required. | 
|  | * | 
|  | *    tlb_remove_page() and tlb_remove_page_size() imply the call to | 
|  | *    tlb_flush_mmu() when required and has no return value. | 
|  | * | 
|  | *    __tlb_remove_folio_pages() is similar to __tlb_remove_page_size(), | 
|  | *    however, instead of removing a single page, assume PAGE_SIZE and remove | 
|  | *    the given number of consecutive pages that are all part of the | 
|  | *    same (large) folio. | 
|  | * | 
|  | *  - tlb_change_page_size() | 
|  | * | 
|  | *    call before __tlb_remove_page*() to set the current page-size; implies a | 
|  | *    possible tlb_flush_mmu() call. | 
|  | * | 
|  | *  - tlb_flush_mmu() / tlb_flush_mmu_tlbonly() | 
|  | * | 
|  | *    tlb_flush_mmu_tlbonly() - does the TLB invalidate (and resets | 
|  | *                              related state, like the range) | 
|  | * | 
|  | *    tlb_flush_mmu() - in addition to the above TLB invalidate, also frees | 
|  | *			whatever pages are still batched. | 
|  | * | 
|  | *  - mmu_gather::fullmm | 
|  | * | 
|  | *    A flag set by tlb_gather_mmu_fullmm() to indicate we're going to free | 
|  | *    the entire mm; this allows a number of optimizations. | 
|  | * | 
|  | *    - We can ignore tlb_{start,end}_vma(); because we don't | 
|  | *      care about ranges. Everything will be shot down. | 
|  | * | 
|  | *    - (RISC) architectures that use ASIDs can cycle to a new ASID | 
|  | *      and delay the invalidation until ASID space runs out. | 
|  | * | 
|  | *  - mmu_gather::need_flush_all | 
|  | * | 
|  | *    A flag that can be set by the arch code if it wants to force | 
|  | *    flush the entire TLB irrespective of the range. For instance | 
|  | *    x86-PAE needs this when changing top-level entries. | 
|  | * | 
|  | * And allows the architecture to provide and implement tlb_flush(): | 
|  | * | 
|  | * tlb_flush() may, in addition to the above mentioned mmu_gather fields, make | 
|  | * use of: | 
|  | * | 
|  | *  - mmu_gather::start / mmu_gather::end | 
|  | * | 
|  | *    which provides the range that needs to be flushed to cover the pages to | 
|  | *    be freed. | 
|  | * | 
|  | *  - mmu_gather::freed_tables | 
|  | * | 
|  | *    set when we freed page table pages | 
|  | * | 
|  | *  - tlb_get_unmap_shift() / tlb_get_unmap_size() | 
|  | * | 
|  | *    returns the smallest TLB entry size unmapped in this range. | 
|  | * | 
|  | * If an architecture does not provide tlb_flush() a default implementation | 
|  | * based on flush_tlb_range() will be used, unless MMU_GATHER_NO_RANGE is | 
|  | * specified, in which case we'll default to flush_tlb_mm(). | 
|  | * | 
|  | * Additionally there are a few opt-in features: | 
|  | * | 
|  | *  MMU_GATHER_PAGE_SIZE | 
|  | * | 
|  | *  This ensures we call tlb_flush() every time tlb_change_page_size() actually | 
|  | *  changes the size and provides mmu_gather::page_size to tlb_flush(). | 
|  | * | 
|  | *  This might be useful if your architecture has size specific TLB | 
|  | *  invalidation instructions. | 
|  | * | 
|  | *  MMU_GATHER_TABLE_FREE | 
|  | * | 
|  | *  This provides tlb_remove_table(), to be used instead of tlb_remove_page() | 
|  | *  for page directores (__p*_free_tlb()). | 
|  | * | 
|  | *  Useful if your architecture has non-page page directories. | 
|  | * | 
|  | *  When used, an architecture is expected to provide __tlb_remove_table() or | 
|  | *  use the generic __tlb_remove_table(), which does the actual freeing of these | 
|  | *  pages. | 
|  | * | 
|  | *  MMU_GATHER_RCU_TABLE_FREE | 
|  | * | 
|  | *  Like MMU_GATHER_TABLE_FREE, and adds semi-RCU semantics to the free (see | 
|  | *  comment below). | 
|  | * | 
|  | *  Useful if your architecture doesn't use IPIs for remote TLB invalidates | 
|  | *  and therefore doesn't naturally serialize with software page-table walkers. | 
|  | * | 
|  | *  MMU_GATHER_NO_FLUSH_CACHE | 
|  | * | 
|  | *  Indicates the architecture has flush_cache_range() but it needs *NOT* be called | 
|  | *  before unmapping a VMA. | 
|  | * | 
|  | *  NOTE: strictly speaking we shouldn't have this knob and instead rely on | 
|  | *	  flush_cache_range() being a NOP, except Sparc64 seems to be | 
|  | *	  different here. | 
|  | * | 
|  | *  MMU_GATHER_MERGE_VMAS | 
|  | * | 
|  | *  Indicates the architecture wants to merge ranges over VMAs; typical when | 
|  | *  multiple range invalidates are more expensive than a full invalidate. | 
|  | * | 
|  | *  MMU_GATHER_NO_RANGE | 
|  | * | 
|  | *  Use this if your architecture lacks an efficient flush_tlb_range(). This | 
|  | *  option implies MMU_GATHER_MERGE_VMAS above. | 
|  | * | 
|  | *  MMU_GATHER_NO_GATHER | 
|  | * | 
|  | *  If the option is set the mmu_gather will not track individual pages for | 
|  | *  delayed page free anymore. A platform that enables the option needs to | 
|  | *  provide its own implementation of the __tlb_remove_page_size() function to | 
|  | *  free pages. | 
|  | * | 
|  | *  This is useful if your architecture already flushes TLB entries in the | 
|  | *  various ptep_get_and_clear() functions. | 
|  | */ | 
|  |  | 
|  | #ifdef CONFIG_MMU_GATHER_TABLE_FREE | 
|  |  | 
|  | struct mmu_table_batch { | 
|  | #ifdef CONFIG_MMU_GATHER_RCU_TABLE_FREE | 
|  | struct rcu_head		rcu; | 
|  | #endif | 
|  | unsigned int		nr; | 
|  | void			*tables[]; | 
|  | }; | 
|  |  | 
|  | #define MAX_TABLE_BATCH		\ | 
|  | ((PAGE_SIZE - sizeof(struct mmu_table_batch)) / sizeof(void *)) | 
|  |  | 
|  | #ifndef __HAVE_ARCH_TLB_REMOVE_TABLE | 
|  | static inline void __tlb_remove_table(void *table) | 
|  | { | 
|  | struct ptdesc *ptdesc = (struct ptdesc *)table; | 
|  |  | 
|  | pagetable_dtor_free(ptdesc); | 
|  | } | 
|  | #endif | 
|  |  | 
|  | extern void tlb_remove_table(struct mmu_gather *tlb, void *table); | 
|  |  | 
|  | #else /* !CONFIG_MMU_GATHER_TABLE_FREE */ | 
|  |  | 
|  | static inline void tlb_remove_page(struct mmu_gather *tlb, struct page *page); | 
|  | /* | 
|  | * Without MMU_GATHER_TABLE_FREE the architecture is assumed to have page based | 
|  | * page directories and we can use the normal page batching to free them. | 
|  | */ | 
|  | static inline void tlb_remove_table(struct mmu_gather *tlb, void *table) | 
|  | { | 
|  | struct ptdesc *ptdesc = (struct ptdesc *)table; | 
|  |  | 
|  | pagetable_dtor(ptdesc); | 
|  | tlb_remove_page(tlb, ptdesc_page(ptdesc)); | 
|  | } | 
|  | #endif /* CONFIG_MMU_GATHER_TABLE_FREE */ | 
|  |  | 
|  | #ifdef CONFIG_MMU_GATHER_RCU_TABLE_FREE | 
|  | /* | 
|  | * This allows an architecture that does not use the linux page-tables for | 
|  | * hardware to skip the TLBI when freeing page tables. | 
|  | */ | 
|  | #ifndef tlb_needs_table_invalidate | 
|  | #define tlb_needs_table_invalidate() (true) | 
|  | #endif | 
|  |  | 
|  | void tlb_remove_table_sync_one(void); | 
|  |  | 
|  | #else | 
|  |  | 
|  | #ifdef tlb_needs_table_invalidate | 
|  | #error tlb_needs_table_invalidate() requires MMU_GATHER_RCU_TABLE_FREE | 
|  | #endif | 
|  |  | 
|  | static inline void tlb_remove_table_sync_one(void) { } | 
|  |  | 
|  | #endif /* CONFIG_MMU_GATHER_RCU_TABLE_FREE */ | 
|  |  | 
|  |  | 
|  | #ifndef CONFIG_MMU_GATHER_NO_GATHER | 
|  | /* | 
|  | * If we can't allocate a page to make a big batch of page pointers | 
|  | * to work on, then just handle a few from the on-stack structure. | 
|  | */ | 
|  | #define MMU_GATHER_BUNDLE	8 | 
|  |  | 
|  | struct mmu_gather_batch { | 
|  | struct mmu_gather_batch	*next; | 
|  | unsigned int		nr; | 
|  | unsigned int		max; | 
|  | struct encoded_page	*encoded_pages[]; | 
|  | }; | 
|  |  | 
|  | #define MAX_GATHER_BATCH	\ | 
|  | ((PAGE_SIZE - sizeof(struct mmu_gather_batch)) / sizeof(void *)) | 
|  |  | 
|  | /* | 
|  | * Limit the maximum number of mmu_gather batches to reduce a risk of soft | 
|  | * lockups for non-preemptible kernels on huge machines when a lot of memory | 
|  | * is zapped during unmapping. | 
|  | * 10K pages freed at once should be safe even without a preemption point. | 
|  | */ | 
|  | #define MAX_GATHER_BATCH_COUNT	(10000UL/MAX_GATHER_BATCH) | 
|  |  | 
|  | extern bool __tlb_remove_page_size(struct mmu_gather *tlb, struct page *page, | 
|  | bool delay_rmap, int page_size); | 
|  | bool __tlb_remove_folio_pages(struct mmu_gather *tlb, struct page *page, | 
|  | unsigned int nr_pages, bool delay_rmap); | 
|  |  | 
|  | #ifdef CONFIG_SMP | 
|  | /* | 
|  | * This both sets 'delayed_rmap', and returns true. It would be an inline | 
|  | * function, except we define it before the 'struct mmu_gather'. | 
|  | */ | 
|  | #define tlb_delay_rmap(tlb) (((tlb)->delayed_rmap = 1), true) | 
|  | extern void tlb_flush_rmaps(struct mmu_gather *tlb, struct vm_area_struct *vma); | 
|  | #endif | 
|  |  | 
|  | #endif | 
|  |  | 
|  | /* | 
|  | * We have a no-op version of the rmap removal that doesn't | 
|  | * delay anything. That is used on S390, which flushes remote | 
|  | * TLBs synchronously, and on UP, which doesn't have any | 
|  | * remote TLBs to flush and is not preemptible due to this | 
|  | * all happening under the page table lock. | 
|  | */ | 
|  | #ifndef tlb_delay_rmap | 
|  | #define tlb_delay_rmap(tlb) (false) | 
|  | static inline void tlb_flush_rmaps(struct mmu_gather *tlb, struct vm_area_struct *vma) { } | 
|  | #endif | 
|  |  | 
|  | /* | 
|  | * struct mmu_gather is an opaque type used by the mm code for passing around | 
|  | * any data needed by arch specific code for tlb_remove_page. | 
|  | */ | 
|  | struct mmu_gather { | 
|  | struct mm_struct	*mm; | 
|  |  | 
|  | #ifdef CONFIG_MMU_GATHER_TABLE_FREE | 
|  | struct mmu_table_batch	*batch; | 
|  | #endif | 
|  |  | 
|  | unsigned long		start; | 
|  | unsigned long		end; | 
|  | /* | 
|  | * we are in the middle of an operation to clear | 
|  | * a full mm and can make some optimizations | 
|  | */ | 
|  | unsigned int		fullmm : 1; | 
|  |  | 
|  | /* | 
|  | * we have performed an operation which | 
|  | * requires a complete flush of the tlb | 
|  | */ | 
|  | unsigned int		need_flush_all : 1; | 
|  |  | 
|  | /* | 
|  | * we have removed page directories | 
|  | */ | 
|  | unsigned int		freed_tables : 1; | 
|  |  | 
|  | /* | 
|  | * Do we have pending delayed rmap removals? | 
|  | */ | 
|  | unsigned int		delayed_rmap : 1; | 
|  |  | 
|  | /* | 
|  | * at which levels have we cleared entries? | 
|  | */ | 
|  | unsigned int		cleared_ptes : 1; | 
|  | unsigned int		cleared_pmds : 1; | 
|  | unsigned int		cleared_puds : 1; | 
|  | unsigned int		cleared_p4ds : 1; | 
|  |  | 
|  | /* | 
|  | * tracks VM_EXEC | VM_HUGETLB in tlb_start_vma | 
|  | */ | 
|  | unsigned int		vma_exec : 1; | 
|  | unsigned int		vma_huge : 1; | 
|  | unsigned int		vma_pfn  : 1; | 
|  |  | 
|  | unsigned int		batch_count; | 
|  |  | 
|  | #ifndef CONFIG_MMU_GATHER_NO_GATHER | 
|  | struct mmu_gather_batch *active; | 
|  | struct mmu_gather_batch	local; | 
|  | struct page		*__pages[MMU_GATHER_BUNDLE]; | 
|  |  | 
|  | #ifdef CONFIG_MMU_GATHER_PAGE_SIZE | 
|  | unsigned int page_size; | 
|  | #endif | 
|  | #endif | 
|  | }; | 
|  |  | 
|  | void tlb_flush_mmu(struct mmu_gather *tlb); | 
|  |  | 
|  | static inline void __tlb_adjust_range(struct mmu_gather *tlb, | 
|  | unsigned long address, | 
|  | unsigned int range_size) | 
|  | { | 
|  | tlb->start = min(tlb->start, address); | 
|  | tlb->end = max(tlb->end, address + range_size); | 
|  | } | 
|  |  | 
|  | static inline void __tlb_reset_range(struct mmu_gather *tlb) | 
|  | { | 
|  | if (tlb->fullmm) { | 
|  | tlb->start = tlb->end = ~0; | 
|  | } else { | 
|  | tlb->start = TASK_SIZE; | 
|  | tlb->end = 0; | 
|  | } | 
|  | tlb->freed_tables = 0; | 
|  | tlb->cleared_ptes = 0; | 
|  | tlb->cleared_pmds = 0; | 
|  | tlb->cleared_puds = 0; | 
|  | tlb->cleared_p4ds = 0; | 
|  | /* | 
|  | * Do not reset mmu_gather::vma_* fields here, we do not | 
|  | * call into tlb_start_vma() again to set them if there is an | 
|  | * intermediate flush. | 
|  | */ | 
|  | } | 
|  |  | 
|  | #ifdef CONFIG_MMU_GATHER_NO_RANGE | 
|  |  | 
|  | #if defined(tlb_flush) | 
|  | #error MMU_GATHER_NO_RANGE relies on default tlb_flush() | 
|  | #endif | 
|  |  | 
|  | /* | 
|  | * When an architecture does not have efficient means of range flushing TLBs | 
|  | * there is no point in doing intermediate flushes on tlb_end_vma() to keep the | 
|  | * range small. We equally don't have to worry about page granularity or other | 
|  | * things. | 
|  | * | 
|  | * All we need to do is issue a full flush for any !0 range. | 
|  | */ | 
|  | static inline void tlb_flush(struct mmu_gather *tlb) | 
|  | { | 
|  | if (tlb->end) | 
|  | flush_tlb_mm(tlb->mm); | 
|  | } | 
|  |  | 
|  | #else /* CONFIG_MMU_GATHER_NO_RANGE */ | 
|  |  | 
|  | #ifndef tlb_flush | 
|  | /* | 
|  | * When an architecture does not provide its own tlb_flush() implementation | 
|  | * but does have a reasonably efficient flush_vma_range() implementation | 
|  | * use that. | 
|  | */ | 
|  | static inline void tlb_flush(struct mmu_gather *tlb) | 
|  | { | 
|  | if (tlb->fullmm || tlb->need_flush_all) { | 
|  | flush_tlb_mm(tlb->mm); | 
|  | } else if (tlb->end) { | 
|  | struct vm_area_struct vma = { | 
|  | .vm_mm = tlb->mm, | 
|  | .vm_flags = (tlb->vma_exec ? VM_EXEC    : 0) | | 
|  | (tlb->vma_huge ? VM_HUGETLB : 0), | 
|  | }; | 
|  |  | 
|  | flush_tlb_range(&vma, tlb->start, tlb->end); | 
|  | } | 
|  | } | 
|  | #endif | 
|  |  | 
|  | #endif /* CONFIG_MMU_GATHER_NO_RANGE */ | 
|  |  | 
|  | static inline void | 
|  | tlb_update_vma_flags(struct mmu_gather *tlb, struct vm_area_struct *vma) | 
|  | { | 
|  | /* | 
|  | * flush_tlb_range() implementations that look at VM_HUGETLB (tile, | 
|  | * mips-4k) flush only large pages. | 
|  | * | 
|  | * flush_tlb_range() implementations that flush I-TLB also flush D-TLB | 
|  | * (tile, xtensa, arm), so it's ok to just add VM_EXEC to an existing | 
|  | * range. | 
|  | * | 
|  | * We rely on tlb_end_vma() to issue a flush, such that when we reset | 
|  | * these values the batch is empty. | 
|  | */ | 
|  | tlb->vma_huge = is_vm_hugetlb_page(vma); | 
|  | tlb->vma_exec = !!(vma->vm_flags & VM_EXEC); | 
|  | tlb->vma_pfn  = !!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)); | 
|  | } | 
|  |  | 
|  | static inline void tlb_flush_mmu_tlbonly(struct mmu_gather *tlb) | 
|  | { | 
|  | /* | 
|  | * Anything calling __tlb_adjust_range() also sets at least one of | 
|  | * these bits. | 
|  | */ | 
|  | if (!(tlb->freed_tables || tlb->cleared_ptes || tlb->cleared_pmds || | 
|  | tlb->cleared_puds || tlb->cleared_p4ds)) | 
|  | return; | 
|  |  | 
|  | tlb_flush(tlb); | 
|  | __tlb_reset_range(tlb); | 
|  | } | 
|  |  | 
|  | static inline void tlb_remove_page_size(struct mmu_gather *tlb, | 
|  | struct page *page, int page_size) | 
|  | { | 
|  | if (__tlb_remove_page_size(tlb, page, false, page_size)) | 
|  | tlb_flush_mmu(tlb); | 
|  | } | 
|  |  | 
|  | 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, struct ptdesc *pt) | 
|  | { | 
|  | tlb_remove_table(tlb, 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 */ |