When we're coalescing, we need to drop the lock on the current free list, as
we've enlarged the block and it may now belong in a different list.
Unfortunately (as shown by repeated tdbtorture -n 8) another coalescing run
can do the coalescing while we've dropped the lock. So for this case, we
use the TDB_COALESCING_MAGIC flag so it doesn't look free.
if (remove_from_list(tdb, b_off, off, r) == -1)
goto err;
if (remove_from_list(tdb, b_off, off, r) == -1)
goto err;
- /* We have to drop this to avoid deadlocks. */
+ r = tdb_access_write(tdb, off, sizeof(*r), true);
+ if (!r)
+ goto err;
+
+ /* We have to drop this to avoid deadlocks, so make sure record
+ * doesn't get coalesced by someone else! */
+ r->magic_and_meta = TDB_COALESCING_MAGIC | zone_bits;
+ r->data_len = end - off - sizeof(struct tdb_used_record);
+ if (tdb_access_commit(tdb, r) != 0)
+ goto err;
+
tdb_unlock_free_bucket(tdb, b_off);
if (add_free_record(tdb, zone_bits, off, end - off) == -1)
tdb_unlock_free_bucket(tdb, b_off);
if (add_free_record(tdb, zone_bits, off, end - off) == -1)