diff options
| -rw-r--r-- | mm/vma.c | 39 |
1 files changed, 27 insertions, 12 deletions
@@ -585,6 +585,31 @@ void validate_mm(struct mm_struct *mm) } #endif /* CONFIG_DEBUG_VM_MAPLE_TREE */ +/* Actually perform the VMA merge operation. */ +static int commit_merge(struct vma_merge_struct *vmg, + struct vm_area_struct *remove) +{ + struct vma_prepare vp; + + init_multi_vma_prep(&vp, vmg->vma, NULL, remove, NULL); + + /* Note: vma iterator must be pointing to 'start'. */ + vma_iter_config(vmg->vmi, vmg->start, vmg->end); + + if (vma_iter_prealloc(vmg->vmi, vmg->vma)) + return -ENOMEM; + + vma_prepare(&vp); + vma_adjust_trans_huge(vmg->vma, vmg->start, vmg->end, 0); + vma_set_range(vmg->vma, vmg->start, vmg->end, vmg->pgoff); + + vma_iter_store(vmg->vmi, vmg->vma); + + vma_complete(&vp, vmg->vmi, vmg->vma->vm_mm); + + return 0; +} + /* * vma_merge_new_range - Attempt to merge a new VMA into address space * @@ -712,7 +737,6 @@ int vma_expand(struct vma_merge_struct *vmg) bool remove_next = false; struct vm_area_struct *vma = vmg->vma; struct vm_area_struct *next = vmg->next; - struct vma_prepare vp; mmap_assert_write_locked(vmg->mm); @@ -727,24 +751,15 @@ int vma_expand(struct vma_merge_struct *vmg) return ret; } - init_multi_vma_prep(&vp, vma, NULL, remove_next ? next : NULL, NULL); /* Not merging but overwriting any part of next is not handled. */ - VM_WARN_ON(next && !vp.remove && + VM_WARN_ON(next && !remove_next && next != vma && vmg->end > next->vm_start); /* Only handles expanding */ VM_WARN_ON(vma->vm_start < vmg->start || vma->vm_end > vmg->end); - /* Note: vma iterator must be pointing to 'start' */ - vma_iter_config(vmg->vmi, vmg->start, vmg->end); - if (vma_iter_prealloc(vmg->vmi, vma)) + if (commit_merge(vmg, remove_next ? next : NULL)) goto nomem; - vma_prepare(&vp); - vma_adjust_trans_huge(vma, vmg->start, vmg->end, 0); - vma_set_range(vma, vmg->start, vmg->end, vmg->pgoff); - vma_iter_store(vmg->vmi, vma); - - vma_complete(&vp, vmg->vmi, vma->vm_mm); return 0; nomem: |