bcachefs: Add missing restart handling to check_topology()

The next patch will add logging of the specific error being corrected in
repair paths to the journal; this means __bch2_fsck_err() can return
transaction restarts in places that previously weren't expecting them.

check_topology() is old code that doesn't use btree iterators for btree
node locking - it'll have to be rewritten in the future to work online.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

diff --git a/fs/bcachefs/btree_gc.c b/fs/bcachefs/btree_gc.c
index 9ddcbe1bda78df102da4aad80b4e2a6dde2241b1..e92cf3928c634bfccfc14366eef8953dc9f1411a 100644 (file)
--- a/fs/bcachefs/btree_gc.c
+++ b/fs/bcachefs/btree_gc.c
@@ -397,7 +397,11 @@ again:
                        continue;
                }
 
-               ret = btree_check_node_boundaries(trans, b, prev, cur, pulled_from_scan);
+               ret = lockrestart_do(trans,
+                       btree_check_node_boundaries(trans, b, prev, cur, pulled_from_scan));
+               if (ret < 0)
+                       goto err;
+
                if (ret == DID_FILL_FROM_SCAN) {
                        new_pass = true;
                        ret = 0;
@@ -438,7 +442,8 @@ again:
 
        if (!ret && !IS_ERR_OR_NULL(prev)) {
                BUG_ON(cur);
-               ret = btree_repair_node_end(trans, b, prev, pulled_from_scan);
+               ret = lockrestart_do(trans,
+                       btree_repair_node_end(trans, b, prev, pulled_from_scan));
                if (ret == DID_FILL_FROM_SCAN) {
                        new_pass = true;
                        ret = 0;
@@ -519,6 +524,46 @@ fsck_err:
        bch2_bkey_buf_exit(&prev_k, c);
        bch2_bkey_buf_exit(&cur_k, c);
        printbuf_exit(&buf);
+       bch_err_fn(c, ret);
+       return ret;
+}
+
+static int bch2_check_root(struct btree_trans *trans, enum btree_id i,
+                          bool *reconstructed_root)
+{
+       struct bch_fs *c = trans->c;
+       struct btree_root *r = bch2_btree_id_root(c, i);
+       struct printbuf buf = PRINTBUF;
+       int ret = 0;
+
+       bch2_btree_id_to_text(&buf, i);
+
+       if (r->error) {
+               bch_info(c, "btree root %s unreadable, must recover from scan", buf.buf);
+
+               r->alive = false;
+               r->error = 0;
+
+               if (!bch2_btree_has_scanned_nodes(c, i)) {
+                       __fsck_err(trans,
+                                  FSCK_CAN_FIX|(!btree_id_important(i) ? FSCK_AUTOFIX : 0),
+                                  btree_root_unreadable_and_scan_found_nothing,
+                                  "no nodes found for btree %s, continue?", buf.buf);
+                       bch2_btree_root_alloc_fake_trans(trans, i, 0);
+               } else {
+                       bch2_btree_root_alloc_fake_trans(trans, i, 1);
+                       bch2_shoot_down_journal_keys(c, i, 1, BTREE_MAX_DEPTH, POS_MIN, SPOS_MAX);
+                       ret = bch2_get_scanned_nodes(c, i, 0, POS_MIN, SPOS_MAX);
+                       if (ret)
+                               goto err;
+               }
+
+               *reconstructed_root = true;
+       }
+err:
+fsck_err:
+       printbuf_exit(&buf);
+       bch_err_fn(c, ret);
        return ret;
 }
 
@@ -526,42 +571,18 @@ int bch2_check_topology(struct bch_fs *c)
 {
        struct btree_trans *trans = bch2_trans_get(c);
        struct bpos pulled_from_scan = POS_MIN;
-       struct printbuf buf = PRINTBUF;
        int ret = 0;
 
        bch2_trans_srcu_unlock(trans);
 
        for (unsigned i = 0; i < btree_id_nr_alive(c) && !ret; i++) {
-               struct btree_root *r = bch2_btree_id_root(c, i);
                bool reconstructed_root = false;
+recover:
+               ret = lockrestart_do(trans, bch2_check_root(trans, i, &reconstructed_root));
+               if (ret)
+                       break;
 
-               printbuf_reset(&buf);
-               bch2_btree_id_to_text(&buf, i);
-
-               if (r->error) {
-reconstruct_root:
-                       bch_info(c, "btree root %s unreadable, must recover from scan", buf.buf);
-
-                       r->alive = false;
-                       r->error = 0;
-
-                       if (!bch2_btree_has_scanned_nodes(c, i)) {
-                               __fsck_err(trans,
-                                          FSCK_CAN_FIX|(!btree_id_important(i) ? FSCK_AUTOFIX : 0),
-                                          btree_root_unreadable_and_scan_found_nothing,
-                                          "no nodes found for btree %s, continue?", buf.buf);
-                               bch2_btree_root_alloc_fake_trans(trans, i, 0);
-                       } else {
-                               bch2_btree_root_alloc_fake_trans(trans, i, 1);
-                               bch2_shoot_down_journal_keys(c, i, 1, BTREE_MAX_DEPTH, POS_MIN, SPOS_MAX);
-                               ret = bch2_get_scanned_nodes(c, i, 0, POS_MIN, SPOS_MAX);
-                               if (ret)
-                                       break;
-                       }
-
-                       reconstructed_root = true;
-               }
-
+               struct btree_root *r = bch2_btree_id_root(c, i);
                struct btree *b = r->b;
 
                btree_node_lock_nopath_nofail(trans, &b->c, SIX_LOCK_read);
@@ -575,17 +596,21 @@ reconstruct_root:
 
                        r->b = NULL;
 
-                       if (!reconstructed_root)
-                               goto reconstruct_root;
+                       if (!reconstructed_root) {
+                               r->error = -EIO;
+                               goto recover;
+                       }
 
+                       struct printbuf buf = PRINTBUF;
+                       bch2_btree_id_to_text(&buf, i);
                        bch_err(c, "empty btree root %s", buf.buf);
+                       printbuf_exit(&buf);
                        bch2_btree_root_alloc_fake_trans(trans, i, 0);
                        r->alive = false;
                        ret = 0;
                }
        }
-fsck_err:
-       printbuf_exit(&buf);
+
        bch2_trans_put(trans);
        return ret;
 }