os/bluestore: reshard on truncate if shards past EOF

This ensure we mop up shards past EOF instead of encoding them
empty and confusing future code (that, say, assumes no shards past
EOF).

Signed-off-by: Sage Weil <sage@redhat.com>

diff --git a/src/os/bluestore/BlueStore.cc b/src/os/bluestore/BlueStore.cc
index e1cb30946f0d62794a5be4c0e8dc869a11761ba9..806fbbfb90a1646f338ee720228b5891268326c0 100644 (file)
--- a/src/os/bluestore/BlueStore.cc
+++ b/src/os/bluestore/BlueStore.cc
@@ -8826,6 +8826,17 @@ int BlueStore::_do_truncate(
     o->extent_map.punch_hole(offset, length, &wctx.old_extents);
     o->extent_map.dirty_range(txc->t, offset, length);
     _wctx_finish(txc, c, o, &wctx);
+
+    // if we have shards past EOF, ask for a reshard
+    if (!o->onode.extent_map_shards.empty() &&
+       o->onode.extent_map_shards.back().offset >= offset) {
+      dout(10) << __func__ << "  request reshard past EOF" << dendl;
+      if (offset) {
+       o->extent_map.request_reshard(offset - 1, offset + length);
+      } else {
+       o->extent_map.request_reshard(0, length);
+      }
+    }
   }
 
   o->onode.size = offset;