Remove hardcode of the EC(2+1) scheme, now it supports EC(k+1), fix some bugs

blockstore_write.cpp

@@ -1,6 +1,6 @@
 #include "blockstore_impl.h"
 
-void blockstore_impl_t::enqueue_write(blockstore_op_t *op)
+bool blockstore_impl_t::enqueue_write(blockstore_op_t *op)
 {
     // Check or assign version number
     bool found = false, deleted = false, is_del = (op->opcode == BS_OP_DELETE);
@@ -40,14 +40,14 @@ void blockstore_impl_t::enqueue_write(blockstore_op_t *op)
         // Invalid version requested
         op->retval = -EINVAL;
         FINISH_OP(op);
-        return;
+        return false;
     }
     if (deleted && is_del)
     {
         // Already deleted
         op->retval = 0;
         FINISH_OP(op);
-        return;
+        return false;
     }
     // Immediately add the operation into dirty_db, so subsequent reads could see it
 #ifdef BLOCKSTORE_DEBUG
@@ -68,6 +68,7 @@ void blockstore_impl_t::enqueue_write(blockstore_op_t *op)
         .len = is_del ? 0 : op->len,
         .journal_sector = 0,
     });
+    return true;
 }
 
 // First step of the write algorithm: dequeue operation and submit initial write(s)