... thus making it much closer to (now unreachable, BTW) IS_ROOT(dentry) case in __d_move(). A bit more and it'll fold in.
Unified · Split
| @@ -2635,38 +2635,34 @@ out_err: · 2634 unmodified lines | |||
| 2635 | * Prepare an anonymous dentry for life in the superblock's dentry tree as a | 2635 | * Prepare an anonymous dentry for life in the superblock's dentry tree as a |
| 2636 | * named dentry in place of the dentry to be replaced. | 2636 | * named dentry in place of the dentry to be replaced. |
| 2637 | */ | 2637 | */ |
| 2638 | static void __d_materialise_dentry(struct dentry *dentry, struct dentry *anon) | 2638 | static void __d_materialise_dentry(struct dentry *dentry, struct dentry *target) |
| 2639 | { | 2639 | { |
| 2640 | struct dentry *dparent; | 2640 | dentry_lock_for_move(dentry, target); |
| 2641 | |||
| 2642 | dentry_lock_for_move(anon, dentry); | ||
| 2643 | 2641 | ||
| 2644 | write_seqcount_begin(&dentry->d_seq); | 2642 | write_seqcount_begin(&dentry->d_seq); |
| 2645 | write_seqcount_begin_nested(&anon->d_seq, DENTRY_D_LOCK_NESTED); | 2643 | write_seqcount_begin_nested(&target->d_seq, DENTRY_D_LOCK_NESTED); |
| 2646 | |||
| 2647 | dparent = dentry->d_parent; | ||
| 2648 | 2644 | ||
| 2649 | switch_names(dentry, anon); | 2645 | switch_names(dentry, target); |
| 2650 | swap(dentry->d_name.hash, anon->d_name.hash); | 2646 | swap(dentry->d_name.hash, target->d_name.hash); |
| 2651 | 2647 | ||
| 2652 | dentry->d_parent = dentry; | 2648 | dentry->d_parent = target->d_parent; |
| 2653 | list_del_init(&dentry->d_u.d_child); | 2649 | target->d_parent = target; |
| 2654 | anon->d_parent = dparent; | 2650 | list_del_init(&target->d_u.d_child); |
| 2655 | list_move(&anon->d_u.d_child, &dparent->d_subdirs); | 2651 | list_move(&dentry->d_u.d_child, &dentry->d_parent->d_subdirs); |
| 2656 | if (likely(!d_unhashed(anon))) { | 2652 | if (likely(!d_unhashed(dentry))) { |
| 2657 | hlist_bl_lock(&anon->d_sb->s_anon); | 2653 | hlist_bl_lock(&dentry->d_sb->s_anon); |
| 2658 | __hlist_bl_del(&anon->d_hash); | 2654 | __hlist_bl_del(&dentry->d_hash); |
| 2659 | anon->d_hash.pprev = NULL; | 2655 | dentry->d_hash.pprev = NULL; |
| 2660 | hlist_bl_unlock(&anon->d_sb->s_anon); | 2656 | hlist_bl_unlock(&dentry->d_sb->s_anon); |
| 2661 | } | 2657 | } |
| 2662 | __d_rehash(anon, d_hash(anon->d_parent, anon->d_name.hash)); | 2658 | __d_rehash(dentry, d_hash(dentry->d_parent, dentry->d_name.hash)); |
| 2663 | 2659 | ||
| 2660 | write_seqcount_end(&target->d_seq); | ||
| 2664 | write_seqcount_end(&dentry->d_seq); | 2661 | write_seqcount_end(&dentry->d_seq); |
| 2665 | write_seqcount_end(&anon->d_seq); | ||
| 2666 | 2662 | ||
| 2667 | dentry_unlock_parents_for_move(anon, dentry); | 2663 | dentry_unlock_parents_for_move(dentry, target); |
| 2664 | spin_unlock(&target->d_lock); | ||
| 2668 | spin_unlock(&dentry->d_lock); | 2665 | spin_unlock(&dentry->d_lock); |
| 2669 | spin_unlock(&anon->d_lock); | ||
| 2670 | } | 2666 | } |
| 2671 | 2667 | ||
| 2672 | /** | 2668 | /** |
| @@ -2714,7 +2710,7 @@ struct dentry *d_splice_alias(struct inode *inode, struct dentry *dentry) · 41 unmodified lines | |||
| 2714 | return ERR_PTR(-EIO); | 2710 | return ERR_PTR(-EIO); |
| 2715 | } | 2711 | } |
| 2716 | write_seqlock(&rename_lock); | 2712 | write_seqlock(&rename_lock); |
| 2717 | __d_materialise_dentry(dentry, new); | 2713 | __d_materialise_dentry(new, dentry); |
| 2718 | write_sequnlock(&rename_lock); | 2714 | write_sequnlock(&rename_lock); |
| 2719 | spin_unlock(&inode->i_lock); | 2715 | spin_unlock(&inode->i_lock); |
| 2720 | security_d_instantiate(new, inode); | 2716 | security_d_instantiate(new, inode); |
| @@ -2775,7 +2771,7 @@ struct dentry *d_materialise_unique(struct dentry *dentry, struct inode *inode) · 54 unmodified lines | |||
| 2775 | } else if (IS_ROOT(alias)) { | 2771 | } else if (IS_ROOT(alias)) { |
| 2776 | /* Is this an anonymous mountpoint that we | 2772 | /* Is this an anonymous mountpoint that we |
| 2777 | * could splice into our tree? */ | 2773 | * could splice into our tree? */ |
| 2778 | __d_materialise_dentry(dentry, alias); | 2774 | __d_materialise_dentry(alias, dentry); |
| 2779 | write_sequnlock(&rename_lock); | 2775 | write_sequnlock(&rename_lock); |
| 2780 | goto found; | 2776 | goto found; |
| 2781 | } else { | 2777 | } else { |