41  * Before encoding a non-upper directory file handle from real layer N, we need
42  * to check if it will be possible to reconnect an overlay dentry from the real
176  * (*) Connecting an overlay dir from real lower dentry is not always
278  * Find or instantiate an overlay dentry from real dentries and index.
360  * Lookup a child overlay dentry to get a connected overlay dentry whose real
361  * dentry is @real. If @real is on upper layer, we lookup a child overlay
362  * dentry with the same name as the real dentry. Otherwise, we need to consult
366 					  struct dentry *real,  in ovl_lookup_real_one()  argument
375 	 * Lookup child overlay dentry by real name. The dir mutex protects us  in ovl_lookup_real_one()
377 	 * real has already been moved to a parent that is not under the  in ovl_lookup_real_one()
379 	 * connected real path from the top.  in ovl_lookup_real_one()
383 	parent = dget_parent(real);  in ovl_lookup_real_one()
388 	 * We also need to take a snapshot of real dentry name to protect us  in ovl_lookup_real_one()
391 	 * pointer because we hold no lock on the real dentry.  in ovl_lookup_real_one()
393 	take_dentry_name_snapshot(&name, real);  in ovl_lookup_real_one()
408 	} else if (ovl_dentry_real_at(this, layer->idx) != real) {  in ovl_lookup_real_one()
420 	pr_warn_ratelimited("failed to lookup one by real (%pd2, layer=%d, connected=%pd2, err=%i)\n",  in ovl_lookup_real_one()
421 			    real, layer->idx, connected, err);  in ovl_lookup_real_one()
427 				      struct dentry *real,
431  * Lookup an indexed or hashed overlay dentry by real inode.
434 					    struct dentry *real,  in ovl_lookup_real_inode()  argument
446 	inode = ovl_lookup_inode(sb, real, !layer->idx);  in ovl_lookup_real_inode()
458 	if (!this && layer->idx && ofs->indexdir && !WARN_ON(!d_is_dir(real))) {  in ovl_lookup_real_inode()
459 		index = ovl_lookup_index(ofs, NULL, real, false);  in ovl_lookup_real_inode()
486 	if (ovl_dentry_real_at(this, layer->idx) != real) {  in ovl_lookup_real_inode()
495  * Lookup an indexed or hashed overlay dentry, whose real dentry is an
496  * ancestor of @real.
499 					       struct dentry *real,  in ovl_lookup_real_ancestor()  argument
505 	if (real == layer->mnt->mnt_root)  in ovl_lookup_real_ancestor()
509 	next = dget(real);  in ovl_lookup_real_ancestor()
515 		 * cache or in index by real inode.  in ovl_lookup_real_ancestor()
527 		 * If @real has been moved out of the layer root directory,  in ovl_lookup_real_ancestor()
528 		 * we will eventully hit the real fs root. This cannot happen  in ovl_lookup_real_ancestor()
547  * Lookup a connected overlay dentry whose real dentry is @real.
548  * If @real is on upper layer, we lookup a child overlay dentry with the same
549  * path the real dentry. Otherwise, we need to consult index for lookup.
552 				      struct dentry *real,  in ovl_lookup_real()  argument
558 	connected = ovl_lookup_real_ancestor(sb, real, layer);  in ovl_lookup_real()
568 		if (real_connected == real)  in ovl_lookup_real()
572 		next = dget(real);  in ovl_lookup_real()
580 			 * If real has been moved out of 'real_connected',  in ovl_lookup_real()
594 			 * If real file has been moved out of the layer root  in ovl_lookup_real()
595 			 * directory, we will eventully hit the real fs root.  in ovl_lookup_real()
618 			 * still an ancestor of 'real'. There is a good chance  in ovl_lookup_real()
624 				this = ovl_lookup_real_ancestor(sb, real,  in ovl_lookup_real()
644 	pr_warn_ratelimited("failed to lookup by real (%pd2, layer=%d, connected=%pd2, err=%i)\n",  in ovl_lookup_real()
645 			    real, layer->idx, connected, err);  in ovl_lookup_real()
651  * Get an overlay dentry from upper/lower real dentries and index.
660 	struct dentry *real = upper ?: (index ?: lowerpath->dentry);  in ovl_get_dentry()  local
663 	 * Obtain a disconnected overlay dentry from a non-dir real dentry  in ovl_get_dentry()
666 	if (!d_is_dir(real))  in ovl_get_dentry()
670 	if ((real->d_flags & DCACHE_DISCONNECTED) || d_unhashed(real))  in ovl_get_dentry()
674 	 * If real dentry is connected and hashed, get a connected overlay  in ovl_get_dentry()
675 	 * dentry whose real dentry is @real.  in ovl_get_dentry()
677 	return ovl_lookup_real(sb, real, layer);  in ovl_get_dentry()