Begin implementation of enqueue/dequeue

blockstore.cpp

@@ -50,7 +50,7 @@ blockstore::~blockstore()
 // main event loop - handle requests
 void blockstore::handle_event(ring_data_t *data)
 {
-    if (initialized != 0)
+    if (initialized != 10)
     {
         if (metadata_init_reader)
         {
@@ -119,6 +119,66 @@ void blockstore::loop()
     }
     else
     {
-        
+        // try to submit ops
+        auto op = submit_queue.begin();
+        while (op != submit_queue.end())
+        {
+            auto cur = op++;
+            if (((*cur)->flags & OP_TYPE_MASK) == OP_READ_DIRTY ||
+                ((*cur)->flags & OP_TYPE_MASK) == OP_READ)
+            {
+                int dequeue_op = dequeue_read(*cur);
+                if (dequeue_op)
+                {
+                    submit_queue.erase(cur);
+                }
+                else if ((*cur)->wait_for == WAIT_SQE)
+                {
+                    // ring is full, stop submission
+                    break;
+                }
+            }
+        }
     }
 }
+
+int blockstore::enqueue_op(blockstore_operation *op)
+{
+    if (op->offset >= block_size || op->len >= block_size-op->offset)
+    {
+        return -EINVAL;
+    }
+    submit_queue.push_back(op);
+    if ((op->flags & OP_TYPE_MASK) == OP_WRITE)
+    {
+        // Assign version number
+        auto dirty_it = dirty_queue.find(op->oid);
+        if (dirty_it != dirty_queue.end())
+        {
+            op->version = (*dirty_it).back().version + 1;
+        }
+        else
+        {
+            auto clean_it = object_db.find(op->oid);
+            if (clean_it != object_db.end())
+            {
+                op->version = (*clean_it).version + 1;
+            }
+            else
+            {
+                op->version = 1;
+            }
+            dirty_it = dirty_queue.emplace(op->oid, dirty_list()).first;
+        }
+        // Immediately add the operation into the dirty queue, so subsequent reads could see it
+        (*dirty_it).push_back((dirty_entry){
+            .version = op->version,
+            .state = ST_IN_FLIGHT,
+            .flags = 0,
+            .location = 0,
+            .offset = op->offset,
+            .size = op->len,
+        });
+    }
+    return 0;
+}