diff options
Diffstat (limited to 'mm/memory.c')
| -rw-r--r-- | mm/memory.c | 30 |
1 files changed, 23 insertions, 7 deletions
diff --git a/mm/memory.c b/mm/memory.c index fbf74112de5b..ca920d1fd314 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -235,10 +235,8 @@ void tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm, unsigned long static void tlb_flush_mmu_tlbonly(struct mmu_gather *tlb) { - if (!tlb->end) - return; - tlb_flush(tlb); + mmu_notifier_invalidate_range(tlb->mm, tlb->start, tlb->end); #ifdef CONFIG_HAVE_RCU_TABLE_FREE tlb_table_flush(tlb); #endif @@ -258,6 +256,9 @@ static void tlb_flush_mmu_free(struct mmu_gather *tlb) void tlb_flush_mmu(struct mmu_gather *tlb) { + if (!tlb->end) + return; + tlb_flush_mmu_tlbonly(tlb); tlb_flush_mmu_free(tlb); } @@ -2220,7 +2221,7 @@ gotten: * seen in the presence of one thread doing SMC and another * thread doing COW. */ - ptep_clear_flush(vma, address, page_table); + ptep_clear_flush_notify(vma, address, page_table); page_add_new_anon_rmap(new_page, vma, address); mem_cgroup_commit_charge(new_page, memcg, false); lru_cache_add_active_or_unevictable(new_page, vma); @@ -2377,12 +2378,12 @@ void unmap_mapping_range(struct address_space *mapping, details.last_index = ULONG_MAX; - i_mmap_lock_read(mapping); + i_mmap_lock_write(mapping); if (unlikely(!RB_EMPTY_ROOT(&mapping->i_mmap))) unmap_mapping_range_tree(&mapping->i_mmap, &details); if (unlikely(!list_empty(&mapping->i_mmap_nonlinear))) unmap_mapping_range_list(&mapping->i_mmap_nonlinear, &details); - i_mmap_unlock_read(mapping); + i_mmap_unlock_write(mapping); } EXPORT_SYMBOL(unmap_mapping_range); @@ -2995,6 +2996,12 @@ static int do_shared_fault(struct mm_struct *mm, struct vm_area_struct *vma, if (set_page_dirty(fault_page)) dirtied = 1; + /* + * Take a local copy of the address_space - page.mapping may be zeroed + * by truncate after unlock_page(). The address_space itself remains + * pinned by vma->vm_file's reference. We rely on unlock_page()'s + * release semantics to prevent the compiler from undoing this copying. + */ mapping = fault_page->mapping; unlock_page(fault_page); if ((dirtied || vma->vm_ops->page_mkwrite) && mapping) { @@ -3188,7 +3195,16 @@ static int handle_pte_fault(struct mm_struct *mm, pte_t entry; spinlock_t *ptl; - entry = ACCESS_ONCE(*pte); + /* + * some architectures can have larger ptes than wordsize, + * e.g.ppc44x-defconfig has CONFIG_PTE_64BIT=y and CONFIG_32BIT=y, + * so READ_ONCE or ACCESS_ONCE cannot guarantee atomic accesses. + * The code below just needs a consistent view for the ifs and + * we later double check anyway with the ptl lock held. So here + * a barrier will do. + */ + entry = *pte; + barrier(); if (!pte_present(entry)) { if (pte_none(entry)) { if (vma->vm_ops) { |