diff --git a/mm/mmap.c b/mm/mmap.c index 304dc085533a..405e0432c78e 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1373,23 +1373,19 @@ unsigned long mmap_region(struct file *file, unsigned long addr, unsigned long merge_start = addr, merge_end = end; bool writable_file_mapping = false; pgoff_t vm_pgoff; - int error; + int error = -ENOMEM; VMA_ITERATOR(vmi, mm, addr); + unsigned long nr_pages, nr_accounted; - /* Check against address space limit. */ - if (!may_expand_vm(mm, vm_flags, len >> PAGE_SHIFT)) { - unsigned long nr_pages; + nr_pages = count_vma_pages_range(mm, addr, end, &nr_accounted); - /* - * MAP_FIXED may remove pages of mappings that intersects with - * requested mapping. Account for the pages it would unmap. - */ - nr_pages = count_vma_pages_range(mm, addr, end); - - if (!may_expand_vm(mm, vm_flags, - (len >> PAGE_SHIFT) - nr_pages)) - return -ENOMEM; - } + /* + * Check against address space limit. + * MAP_FIXED may remove pages of mappings that intersects with requested + * mapping. Account for the pages it would unmap. + */ + if (!may_expand_vm(mm, vm_flags, (len >> PAGE_SHIFT) - nr_pages)) + return -ENOMEM; /* Find the first overlapping VMA */ vma = vma_find(&vmi, end); @@ -1403,13 +1399,6 @@ unsigned long mmap_region(struct file *file, unsigned long addr, if (error) goto gather_failed; - /* Remove any existing mappings from the vma tree */ - error = vma_iter_clear_gfp(&vmi, addr, end, GFP_KERNEL); - if (error) - goto clear_tree_failed; - - /* Unmap any existing mapping in the area */ - vms_complete_munmap_vmas(&vms, &mas_detach); next = vms.next; prev = vms.prev; vma = NULL; @@ -1425,8 +1414,10 @@ unsigned long mmap_region(struct file *file, unsigned long addr, */ if (accountable_mapping(file, vm_flags)) { charged = len >> PAGE_SHIFT; + charged -= nr_accounted; if (security_vm_enough_memory_mm(mm, charged)) - return -ENOMEM; + goto abort_munmap; + vms.nr_accounted = 0; vm_flags |= VM_ACCOUNT; } @@ -1475,10 +1466,8 @@ cannot_expand: * not unmapped, but the maps are removed from the list. */ vma = vm_area_alloc(mm); - if (!vma) { - error = -ENOMEM; + if (!vma) goto unacct_error; - } vma_iter_config(&vmi, addr, end); vma_set_range(vma, addr, end, pgoff); @@ -1487,6 +1476,11 @@ cannot_expand: if (file) { vma->vm_file = get_file(file); + /* + * call_mmap() may map PTE, so ensure there are no existing PTEs + * call the vm_ops close function if one exists. + */ + vms_clean_up_area(&vms, &mas_detach, true); error = call_mmap(file, vma); if (error) goto unmap_and_free_vma; @@ -1577,6 +1571,9 @@ unmap_writable: expanded: perf_event_mmap(vma); + /* Unmap any existing mapping in the area */ + vms_complete_munmap_vmas(&vms, &mas_detach); + vm_stat_account(mm, vm_flags, len >> PAGE_SHIFT); if (vm_flags & VM_LOCKED) { if ((vm_flags & VM_SPECIAL) || vma_is_dax(vma) || @@ -1605,7 +1602,7 @@ expanded: return addr; close_and_free_vma: - if (file && vma->vm_ops && vma->vm_ops->close) + if (file && !vms.closed_vm_ops && vma->vm_ops && vma->vm_ops->close) vma->vm_ops->close(vma); if (file || vma->vm_file) { @@ -1625,9 +1622,9 @@ unacct_error: if (charged) vm_unacct_memory(charged); -clear_tree_failed: - if (vms.vma_count) - abort_munmap_vmas(&mas_detach); +abort_munmap: + if (vms.nr_pages) + abort_munmap_vmas(&mas_detach, vms.closed_vm_ops); gather_failed: validate_mm(mm); return error; @@ -1960,7 +1957,7 @@ void exit_mmap(struct mm_struct *mm) do { if (vma->vm_flags & VM_ACCOUNT) nr_accounted += vma_pages(vma); - remove_vma(vma, true); + remove_vma(vma, /* unreachable = */ true, /* closed = */ false); count++; cond_resched(); vma = vma_next(&vmi); diff --git a/mm/vma.c b/mm/vma.c index 83c5c46c67b9..648c58da8ad4 100644 --- a/mm/vma.c +++ b/mm/vma.c @@ -136,10 +136,10 @@ can_vma_merge_after(struct vm_area_struct *vma, unsigned long vm_flags, /* * Close a vm structure and free it. */ -void remove_vma(struct vm_area_struct *vma, bool unreachable) +void remove_vma(struct vm_area_struct *vma, bool unreachable, bool closed) { might_sleep(); - if (vma->vm_ops && vma->vm_ops->close) + if (!closed && vma->vm_ops && vma->vm_ops->close) vma->vm_ops->close(vma); if (vma->vm_file) fput(vma->vm_file); @@ -521,7 +521,6 @@ int vma_expand(struct vma_iterator *vmi, struct vm_area_struct *vma, vma_iter_store(vmi, vma); vma_complete(&vp, vmi, vma->vm_mm); - validate_mm(vma->vm_mm); return 0; nomem: @@ -645,11 +644,14 @@ again: uprobe_mmap(vp->insert); } -static void vms_complete_pte_clear(struct vma_munmap_struct *vms, - struct ma_state *mas_detach, bool mm_wr_locked) +static inline void vms_clear_ptes(struct vma_munmap_struct *vms, + struct ma_state *mas_detach, bool mm_wr_locked) { struct mmu_gather tlb; + if (!vms->clear_ptes) /* Nothing to do */ + return; + /* * We can free page tables without write-locking mmap_lock because VMAs * were isolated before we downgraded mmap_lock. @@ -658,11 +660,31 @@ static void vms_complete_pte_clear(struct vma_munmap_struct *vms, lru_add_drain(); tlb_gather_mmu(&tlb, vms->mm); update_hiwater_rss(vms->mm); - unmap_vmas(&tlb, mas_detach, vms->vma, vms->start, vms->end, vms->vma_count, mm_wr_locked); + unmap_vmas(&tlb, mas_detach, vms->vma, vms->start, vms->end, + vms->vma_count, mm_wr_locked); + mas_set(mas_detach, 1); /* start and end may be different if there is no prev or next vma. */ - free_pgtables(&tlb, mas_detach, vms->vma, vms->unmap_start, vms->unmap_end, mm_wr_locked); + free_pgtables(&tlb, mas_detach, vms->vma, vms->unmap_start, + vms->unmap_end, mm_wr_locked); tlb_finish_mmu(&tlb); + vms->clear_ptes = false; +} + +void vms_clean_up_area(struct vma_munmap_struct *vms, + struct ma_state *mas_detach, bool mm_wr_locked) +{ + struct vm_area_struct *vma; + + if (!vms->nr_pages) + return; + + vms_clear_ptes(vms, mas_detach, mm_wr_locked); + mas_set(mas_detach, 0); + mas_for_each(mas_detach, vma, ULONG_MAX) + if (vma->vm_ops && vma->vm_ops->close) + vma->vm_ops->close(vma); + vms->closed_vm_ops = true; } /* @@ -686,7 +708,10 @@ void vms_complete_munmap_vmas(struct vma_munmap_struct *vms, if (vms->unlock) mmap_write_downgrade(mm); - vms_complete_pte_clear(vms, mas_detach, !vms->unlock); + if (!vms->nr_pages) + return; + + vms_clear_ptes(vms, mas_detach, !vms->unlock); /* Update high watermark before we lower total_vm */ update_hiwater_vm(mm); /* Stat accounting */ @@ -702,7 +727,7 @@ void vms_complete_munmap_vmas(struct vma_munmap_struct *vms, /* Remove and clean up vmas */ mas_set(mas_detach, 0); mas_for_each(mas_detach, vma, ULONG_MAX) - remove_vma(vma, false); + remove_vma(vma, /* = */ false, vms->closed_vm_ops); vm_unacct_memory(vms->nr_accounted); validate_mm(mm); @@ -846,13 +871,14 @@ int vms_gather_munmap_vmas(struct vma_munmap_struct *vms, while (vma_iter_addr(vms->vmi) > vms->start) vma_iter_prev_range(vms->vmi); + vms->clear_ptes = true; return 0; userfaultfd_error: munmap_gather_failed: end_split_failed: modify_vma_failed: - abort_munmap_vmas(mas_detach); + abort_munmap_vmas(mas_detach, /* closed = */ false); start_split_failed: map_count_exceeded: return error; @@ -897,7 +923,7 @@ int do_vmi_align_munmap(struct vma_iterator *vmi, struct vm_area_struct *vma, return 0; clear_tree_failed: - abort_munmap_vmas(&mas_detach); + abort_munmap_vmas(&mas_detach, /* closed = */ false); gather_failed: validate_mm(mm); return error; @@ -1615,17 +1641,21 @@ bool vma_wants_writenotify(struct vm_area_struct *vma, pgprot_t vm_page_prot) } unsigned long count_vma_pages_range(struct mm_struct *mm, - unsigned long addr, unsigned long end) + unsigned long addr, unsigned long end, + unsigned long *nr_accounted) { VMA_ITERATOR(vmi, mm, addr); struct vm_area_struct *vma; unsigned long nr_pages = 0; + *nr_accounted = 0; for_each_vma_range(vmi, vma, end) { unsigned long vm_start = max(addr, vma->vm_start); unsigned long vm_end = min(end, vma->vm_end); nr_pages += PHYS_PFN(vm_end - vm_start); + if (vma->vm_flags & VM_ACCOUNT) + *nr_accounted += PHYS_PFN(vm_end - vm_start); } return nr_pages; diff --git a/mm/vma.h b/mm/vma.h index 82ba48174341..64b44f5a0a11 100644 --- a/mm/vma.h +++ b/mm/vma.h @@ -48,6 +48,8 @@ struct vma_munmap_struct { unsigned long stack_vm; unsigned long data_vm; bool unlock; /* Unlock after the munmap */ + bool clear_ptes; /* If there are outstanding PTE to be cleared */ + bool closed_vm_ops; /* call_mmap() was encountered, so vmas may be closed */ }; #ifdef CONFIG_DEBUG_VM_MAPLE_TREE @@ -96,14 +98,13 @@ static inline void init_vma_munmap(struct vma_munmap_struct *vms, unsigned long start, unsigned long end, struct list_head *uf, bool unlock) { + vms->mm = current->mm; vms->vmi = vmi; vms->vma = vma; if (vma) { - vms->mm = vma->vm_mm; vms->start = start; vms->end = end; } else { - vms->mm = NULL; vms->start = vms->end = 0; } vms->unlock = unlock; @@ -113,6 +114,8 @@ static inline void init_vma_munmap(struct vma_munmap_struct *vms, vms->exec_vm = vms->stack_vm = vms->data_vm = 0; vms->unmap_start = FIRST_USER_ADDRESS; vms->unmap_end = USER_PGTABLES_CEILING; + vms->clear_ptes = false; + vms->closed_vm_ops = false; } #endif @@ -122,18 +125,24 @@ int vms_gather_munmap_vmas(struct vma_munmap_struct *vms, void vms_complete_munmap_vmas(struct vma_munmap_struct *vms, struct ma_state *mas_detach); +void vms_clean_up_area(struct vma_munmap_struct *vms, + struct ma_state *mas_detach, bool mm_wr_locked); + /* * abort_munmap_vmas - Undo any munmap work and free resources * * Reattach any detached vmas and free up the maple tree used to track the vmas. */ -static inline void abort_munmap_vmas(struct ma_state *mas_detach) +static inline void abort_munmap_vmas(struct ma_state *mas_detach, bool closed) { struct vm_area_struct *vma; mas_set(mas_detach, 0); - mas_for_each(mas_detach, vma, ULONG_MAX) + mas_for_each(mas_detach, vma, ULONG_MAX) { vma_mark_detached(vma, false); + if (closed && vma->vm_ops && vma->vm_ops->open) + vma->vm_ops->open(vma); + } __mt_destroy(mas_detach->tree); } @@ -147,7 +156,7 @@ int do_vmi_munmap(struct vma_iterator *vmi, struct mm_struct *mm, unsigned long start, size_t len, struct list_head *uf, bool unlock); -void remove_vma(struct vm_area_struct *vma, bool unreachable); +void remove_vma(struct vm_area_struct *vma, bool unreachable, bool closed); void unmap_region(struct ma_state *mas, struct vm_area_struct *vma, struct vm_area_struct *prev, struct vm_area_struct *next); @@ -261,7 +270,8 @@ bool vma_wants_writenotify(struct vm_area_struct *vma, pgprot_t vm_page_prot); int mm_take_all_locks(struct mm_struct *mm); void mm_drop_all_locks(struct mm_struct *mm); unsigned long count_vma_pages_range(struct mm_struct *mm, - unsigned long addr, unsigned long end); + unsigned long addr, unsigned long end, + unsigned long *nr_accounted); static inline bool vma_wants_manual_pte_write_upgrade(struct vm_area_struct *vma) {