13 #include "snapshot.h"
18  * Snapshot trees:
20  * Keys in BTREE_ID_snapshot_trees identify a whole tree of snapshot nodes; they
21  * exist to provide a stable identifier for the whole lifetime of a snapshot
30 	prt_printf(out, "subvol %u root snapshot %u",  in bch2_snapshot_tree_to_text()
93 /* Snapshot nodes: */
355 				       BTREE_ITER_with_updates, snapshot, s);  in bch2_snapshot_lookup()
427 		if (!bch2_snapshot_is_ancestor(c, le32_to_cpu(s.v->snapshot), snapshot_root))  in bch2_snapshot_tree_master_subvol()
476 					 POS(0, root_id), 0, snapshot);  in check_snapshot_tree()
488 			"snapshot tree points to missing/incorrect snapshot:\n%s",  in check_snapshot_tree()
508 			"snapshot tree points to missing subvolume:\n%s",  in check_snapshot_tree()
512 						le32_to_cpu(subvol.snapshot),  in check_snapshot_tree()
515 			"snapshot tree points to subvolume that does not point to snapshot in this tree:\n%s",  in check_snapshot_tree()
520 			"snapshot tree points to snapshot subvolume:\n%s",  in check_snapshot_tree()
554  * For each snapshot_tree, make sure it points to the root of a snapshot tree
555  * and that snapshot entry points back to it, or delete it.
557  * And, make sure it points to a subvolume within that snapshot tree, or correct
558  * it to point to the oldest subvolume within that snapshot tree.
573  * Look up snapshot tree for @tree_id and find root,
623  * snapshot_tree pointer was incorrect: look up root snapshot node, make sure
642 			       BTREE_ITER_with_updates, snapshot);  in snapshot_tree_ptr_repair()
654 		u = bch2_bkey_make_mut_typed(trans, &root_iter, &root.s_c, 0, snapshot);  in snapshot_tree_ptr_repair()
668 		u = bch2_bkey_make_mut_typed(trans, iter, &k, 0, snapshot);  in snapshot_tree_ptr_repair()
706 			bch_err(c, "snapshot with nonexistent parent:\n  %s",  in check_snapshot()
713 			bch_err(c, "snapshot parent %u missing pointer to child %llu",  in check_snapshot()
725 			bch_err(c, "snapshot node %llu has nonexistent child %u",  in check_snapshot()
731 			bch_err(c, "snapshot child %u has wrong parent (got %u should be %llu)",  in check_snapshot()
745 			bch_err(c, "snapshot points to nonexistent subvolume:\n  %s",  in check_snapshot()
750 		if (BCH_SNAPSHOT_SUBVOL(&s) != (le32_to_cpu(subvol.snapshot) == k.k->p.offset)) {  in check_snapshot()
751 			bch_err(c, "snapshot node %llu has wrong BCH_SNAPSHOT_SUBVOL",  in check_snapshot()
759 				"snapshot should not point to subvol:\n%s",  in check_snapshot()
761 			u = bch2_bkey_make_mut_typed(trans, iter, &k, 0, snapshot);  in check_snapshot()
777 			"snapshot points to missing/incorrect tree:\n%s",  in check_snapshot()
789 			"snapshot with incorrect depth field, should be %u:\n%s",  in check_snapshot()
791 		u = bch2_bkey_make_mut_typed(trans, iter, &k, 0, snapshot);  in check_snapshot()
806 			"snapshot with bad skiplist field:\n%s",  in check_snapshot()
808 		u = bch2_bkey_make_mut_typed(trans, iter, &k, 0, snapshot);  in check_snapshot()
870 	struct bkey_i_snapshot *snapshot = bch2_trans_kmalloc(trans, sizeof(*snapshot));  in check_snapshot_exists()  local
871 	ret = PTR_ERR_OR_ZERO(snapshot);  in check_snapshot_exists()
875 	bkey_snapshot_init(&snapshot->k_i);  in check_snapshot_exists()
876 	snapshot->k.p		= POS(0, id);  in check_snapshot_exists()
877 	snapshot->v.tree	= cpu_to_le32(tree_id);  in check_snapshot_exists()
878 	snapshot->v.btime.lo	= cpu_to_le64(bch2_current_time(c));  in check_snapshot_exists()
882 		if (le32_to_cpu(bkey_s_c_to_subvolume(k).v->snapshot) == id) {  in check_snapshot_exists()
883 			snapshot->v.subvol = cpu_to_le32(k.k->p.offset);  in check_snapshot_exists()
884 			SET_BCH_SNAPSHOT_SUBVOL(&snapshot->v, true);  in check_snapshot_exists()
890 	return  bch2_btree_insert_trans(trans, BTREE_ID_snapshots, &snapshot->k_i, 0) ?:  in check_snapshot_exists()
892 				   bkey_s_c_null, bkey_i_to_s(&snapshot->k_i), 0);  in check_snapshot_exists()
895 /* Figure out which snapshot nodes belong in the same tree: */
960 	return snapshot_list_add_nodup(c, &r->cur_ids, pos.snapshot);  in get_snapshot_trees()
992 					"snapshot node %u from tree %s missing, recreate?", *id, buf.buf)) {  in bch2_reconstruct_snapshots()
994 					bch_err(c, "cannot reconstruct snapshot trees with multiple nodes");  in bch2_reconstruct_snapshots()
1023 	if (fsck_err_on(!bch2_snapshot_exists(c, k.k->p.snapshot),  in bch2_check_key_has_snapshot()
1025 			"key in missing snapshot %s, delete?",  in bch2_check_key_has_snapshot()
1037  * Mark a snapshot as deleted, for future cleanup:
1045 				    0, snapshot);  in bch2_snapshot_node_set_deleted()
1049 					trans->c, "missing snapshot %u", id);  in bch2_snapshot_node_set_deleted()
1083 				     BTREE_ITER_intent, snapshot);  in bch2_snapshot_node_delete()
1086 				"missing snapshot %u", id);  in bch2_snapshot_node_delete()
1101 				     0, snapshot);  in bch2_snapshot_node_delete()
1104 					"missing snapshot %u", parent_id);  in bch2_snapshot_node_delete()
1114 					"snapshot %u missing child pointer to %u",  in bch2_snapshot_node_delete()
1128 				     0, snapshot);  in bch2_snapshot_node_delete()
1131 					"missing snapshot %u", child_id);  in bch2_snapshot_node_delete()
1146 		 * We're deleting the root of a snapshot tree: update the  in bch2_snapshot_node_delete()
1148 		 * this is the last snapshot ID in this tree:  in bch2_snapshot_node_delete()
1209 		n = bch2_bkey_alloc(trans, &iter, 0, snapshot);  in create_snapids()
1241  * Create new snapshot IDs as children of an existing snapshot ID:
1254 			0, snapshot);  in bch2_snapshot_node_create_children()
1258 			bch_err(trans->c, "snapshot %u not found", parent);  in bch2_snapshot_node_create_children()
1263 		bch_err(trans->c, "Trying to add child snapshot nodes to parent that already has children");  in bch2_snapshot_node_create_children()
1283  * Create a snapshot node that is the root of a new tree:
1322  * If we have an unlinked inode in an internal snapshot node, and the inode
1329  * also: unlinked inode in internal snapshot appears to not be getting deleted
1334  * for a key in an interior snapshot node that needs work to be done that
1336  * that key to snapshot leaf nodes, where we can mutate it
1395 	if (snapshot_list_has_id(delete_leaves, k.k->p.snapshot))  in delete_dead_snapshots_process_key()
1399 	u32 live_child = interior_delete_has_id(delete_interior, k.k->p.snapshot);  in delete_dead_snapshots_process_key()
1406 		new->k.p.snapshot = live_child;  in delete_dead_snapshots_process_key()
1431  * For a given snapshot, if it doesn't have a subvolume that points to it, and
1432  * it doesn't have child snapshot nodes - it's now redundant and we can mark it
1465 			bch_err(c, "error finding live child of snapshot %u", d.id);  in check_should_delete_snapshot()
1507 	s = bch2_bkey_make_mut_noupdate_typed(trans, k, snapshot);  in bch2_fix_child_of_deleted_snapshot()
1559 	 * For every snapshot node: If we have no live children and it's not  in bch2_delete_dead_snapshots()
1614 			bch_err_msg(c, ret, "deleting snapshot %u", *i);  in bch2_delete_dead_snapshots()
1635 			bch_err_msg(c, ret, "deleting snapshot %u", i->id);  in bch2_delete_dead_snapshots()
1685 		if (bch2_snapshot_is_ancestor(c, k.k->p.snapshot, pos.snapshot)) {  in __bch2_key_has_snapshot_overwrites()
1730 	 * otherwise, we could end up deleting keys with missing snapshot nodes  in bch2_snapshots_read()