summaryrefslogtreecommitdiff
path: root/fs/bcachefs/snapshot.c
diff options
context:
space:
mode:
authorKent Overstreet <kent.overstreet@linux.dev>2024-10-09 21:28:11 -0400
committerKent Overstreet <kent.overstreet@linux.dev>2024-10-12 05:02:48 -0400
commitc986dd7ecba185ad2a36b0815940f34deb2a8170 (patch)
treee9a1899c7906d265bf0c4f53c737d8f7e7f6d3c9 /fs/bcachefs/snapshot.c
parent9183c2b11e93f16dfd89a7fa09ec50c0be71f15a (diff)
bcachefs: Improve check_snapshot_exists()
Check if we have snapshot_trees or subvolumes that refer to the snapshot node being reconstructed, and use them. With this, the kill_btree_root test that blows away the snapshots btree now passes, and we're able to successfully reconstruct. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Diffstat (limited to 'fs/bcachefs/snapshot.c')
-rw-r--r--fs/bcachefs/snapshot.c32
1 files changed, 30 insertions, 2 deletions
diff --git a/fs/bcachefs/snapshot.c b/fs/bcachefs/snapshot.c
index 9f4d13faf7aa..ae57638506c3 100644
--- a/fs/bcachefs/snapshot.c
+++ b/fs/bcachefs/snapshot.c
@@ -905,12 +905,30 @@ static int check_snapshot_exists(struct btree_trans *trans, u32 id)
if (bch2_snapshot_equiv(c, id))
return 0;
- /* 0 is an invalid tree ID */
+ /* Do we need to reconstruct the snapshot_tree entry as well? */
+ struct btree_iter iter;
+ struct bkey_s_c k;
+ int ret = 0;
u32 tree_id = 0;
- int ret = bch2_snapshot_tree_create(trans, id, 0, &tree_id);
+
+ for_each_btree_key_norestart(trans, iter, BTREE_ID_snapshot_trees, POS_MIN,
+ 0, k, ret) {
+ if (le32_to_cpu(bkey_s_c_to_snapshot_tree(k).v->root_snapshot) == id) {
+ tree_id = k.k->p.offset;
+ break;
+ }
+ }
+ bch2_trans_iter_exit(trans, &iter);
+
if (ret)
return ret;
+ if (!tree_id) {
+ ret = bch2_snapshot_tree_create(trans, id, 0, &tree_id);
+ if (ret)
+ return ret;
+ }
+
struct bkey_i_snapshot *snapshot = bch2_trans_kmalloc(trans, sizeof(*snapshot));
ret = PTR_ERR_OR_ZERO(snapshot);
if (ret)
@@ -921,6 +939,16 @@ static int check_snapshot_exists(struct btree_trans *trans, u32 id)
snapshot->v.tree = cpu_to_le32(tree_id);
snapshot->v.btime.lo = cpu_to_le64(bch2_current_time(c));
+ for_each_btree_key_norestart(trans, iter, BTREE_ID_subvolumes, POS_MIN,
+ 0, k, ret) {
+ if (le32_to_cpu(bkey_s_c_to_subvolume(k).v->snapshot) == id) {
+ snapshot->v.subvol = cpu_to_le32(k.k->p.offset);
+ SET_BCH_SNAPSHOT_SUBVOL(&snapshot->v, true);
+ break;
+ }
+ }
+ bch2_trans_iter_exit(trans, &iter);
+
return bch2_btree_insert_trans(trans, BTREE_ID_snapshots, &snapshot->k_i, 0) ?:
bch2_mark_snapshot(trans, BTREE_ID_snapshots, 0,
bkey_s_c_null, bkey_i_to_s(&snapshot->k_i), 0) ?: