diff options
Diffstat (limited to 'include/asm-generic/tlb.h')
| -rw-r--r-- | include/asm-generic/tlb.h | 109 |
1 files changed, 67 insertions, 42 deletions
diff --git a/include/asm-generic/tlb.h b/include/asm-generic/tlb.h index 709830274b75..1fff717cae51 100644 --- a/include/asm-generic/tlb.h +++ b/include/asm-generic/tlb.h @@ -58,6 +58,11 @@ * Defaults to flushing at tlb_end_vma() to reset the range; helps when * there's large holes between the VMAs. * + * - tlb_free_vmas() + * + * tlb_free_vmas() marks the start of unlinking of one or more vmas + * and freeing page-tables. + * * - tlb_remove_table() * * tlb_remove_table() is the basic primitive to free page-table directories @@ -67,22 +72,21 @@ * * See also MMU_GATHER_TABLE_FREE and MMU_GATHER_RCU_TABLE_FREE. * - * - tlb_remove_page() / __tlb_remove_page() - * - tlb_remove_page_size() / __tlb_remove_page_size() - * - __tlb_remove_folio_pages() + * - tlb_remove_page() / tlb_remove_page_size() + * - __tlb_remove_folio_pages() / __tlb_remove_page_size() + * - __tlb_remove_folio_pages_size() * - * __tlb_remove_page_size() is the basic primitive that queues a page for - * freeing. __tlb_remove_page() assumes PAGE_SIZE. Both will return a - * boolean indicating if the queue is (now) full and a call to - * tlb_flush_mmu() is required. + * __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(), however, - * instead of removing a single page, remove the given number of consecutive - * pages that are all part of the same (large) folio: just like calling - * __tlb_remove_page() on each page individually. + * __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() * @@ -153,8 +157,9 @@ * * Useful if your architecture has non-page page directories. * - * When used, an architecture is expected to provide __tlb_remove_table() - * which does the actual freeing of these pages. + * 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 * @@ -207,16 +212,31 @@ struct mmu_table_batch { #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_HAVE_TABLE_FREE */ +#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. */ -#define tlb_remove_table(tlb, page) tlb_remove_page((tlb), (page)) +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 @@ -449,7 +469,12 @@ tlb_update_vma_flags(struct mmu_gather *tlb, struct vm_area_struct *vma) */ 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)); + + /* + * Track if there's at least one VM_PFNMAP/VM_MIXEDMAP vma + * in the tracked range, see tlb_free_vmas(). + */ + tlb->vma_pfn |= !!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)); } static inline void tlb_flush_mmu_tlbonly(struct mmu_gather *tlb) @@ -473,32 +498,16 @@ static inline void tlb_remove_page_size(struct mmu_gather *tlb, tlb_flush_mmu(tlb); } -static __always_inline bool __tlb_remove_page(struct mmu_gather *tlb, - 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) +static inline void tlb_remove_ptdesc(struct mmu_gather *tlb, struct ptdesc *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) { @@ -549,22 +558,38 @@ static inline void tlb_start_vma(struct mmu_gather *tlb, struct vm_area_struct * static inline void tlb_end_vma(struct mmu_gather *tlb, struct vm_area_struct *vma) { + if (tlb->fullmm || IS_ENABLED(CONFIG_MMU_GATHER_MERGE_VMAS)) + return; + + /* + * Do a TLB flush and reset the range at VMA boundaries; this avoids + * the ranges growing with the unused space between consecutive VMAs, + * but also the mmu_gather::vma_* flags from tlb_start_vma() rely on + * this. + */ + tlb_flush_mmu_tlbonly(tlb); +} + +static inline void tlb_free_vmas(struct mmu_gather *tlb) +{ 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. + * page mapcount -- there might not be page-frames for these PFNs + * after all. + * + * Specifically() there is a race between munmap() and + * unmap_mapping_range(), where munmap() will unlink the VMA, such + * that unmap_mapping_range() will no longer observe the VMA and + * no-op, without observing the TLBI, returning prematurely. + * + * So if we're about to unlink such a VMA, and we have pending + * TLBI for such a vma, flush things now. */ - 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. - */ + if (tlb->vma_pfn) tlb_flush_mmu_tlbonly(tlb); - } } /* |