MINOR: quic: extract qc_stream_buf free in a dedicated function

On ACK reception, data are removed from buffer via qc_stream_desc_ack().
The buffer can be freed if no more data are left. A new slot is also
accounted in buffer connection pool. Extract this operation in a
dedicated private function qc_stream_buf_free().

This change should have no functional change. However it will be useful
for the next patch which needs to remove a buffer from another function.

This patch is necessary for the following bugfix. As such, it must be
backported with it up to 2.6.

diff --git a/src/quic_stream.c b/src/quic_stream.c
index da86e04ff996a1bf94a214c318f3f4cd4cc7e02c..727636b06a1465b81e84bd04474cc96f5db42b8c 100644 (file)
--- a/src/quic_stream.c
+++ b/src/quic_stream.c
@@ -17,6 +17,34 @@ DECLARE_STATIC_POOL(pool_head_quic_stream_buf, "qc_stream_buf",
                     sizeof(struct qc_stream_buf));
 
 
+static void qc_stream_buf_free(struct qc_stream_desc *stream,
+                               struct qc_stream_buf **stream_buf)
+{
+       struct quic_conn *qc = stream->qc;
+       struct buffer *buf = &(*stream_buf)->buf;
+
+       LIST_DEL_INIT(&(*stream_buf)->list);
+       if (*stream_buf == stream->buf) {
+               /* current buf must always be last entry in buflist */
+               BUG_ON(!LIST_ISEMPTY(&stream->buf_list));
+               stream->buf = NULL;
+       }
+
+       b_free(buf);
+       offer_buffers(NULL, 1);
+       pool_free(pool_head_quic_stream_buf, *stream_buf);
+       *stream_buf = NULL;
+
+       /* notify MUX about available buffers. */
+       --qc->stream_buf_count;
+       if (qc->mux_state == QC_MUX_READY) {
+               if (qc->qcc->flags & QC_CF_CONN_FULL) {
+                       qc->qcc->flags &= ~QC_CF_CONN_FULL;
+                       tasklet_wakeup(qc->qcc->wait_event.tasklet);
+               }
+       }
+}
+
 /* Allocate a new stream descriptor with id <id>. The caller is responsible to
  * store the stream in the appropriate tree. -1 special value must be used for
  * a CRYPTO data stream, the type being ignored.
@@ -92,7 +120,6 @@ int qc_stream_desc_ack(struct qc_stream_desc **stream, size_t offset, size_t len
 {
        struct qc_stream_desc *s = *stream;
        struct qc_stream_buf *stream_buf;
-       struct quic_conn *qc = s->qc;
        struct buffer *buf;
        size_t diff;
 
@@ -110,39 +137,17 @@ int qc_stream_desc_ack(struct qc_stream_desc **stream, size_t offset, size_t len
        s->ack_offset += diff;
        b_del(buf, diff);
 
-       /* nothing more to do if buf still not empty. */
-       if (b_data(buf))
-               return diff;
-
-       /* buf is empty and can now be freed. Do not forget to reset current
-        * buf ptr if we were working on it.
-        */
-       LIST_DELETE(&stream_buf->list);
-       if (stream_buf == s->buf) {
-               /* current buf must always be last entry in buflist */
-               BUG_ON(!LIST_ISEMPTY(&s->buf_list));
-               s->buf = NULL;
-       }
-
-       b_free(buf);
-       pool_free(pool_head_quic_stream_buf, stream_buf);
-       offer_buffers(NULL, 1);
+       /* Free oldest buffer if all data acknowledged. */
+       if (!b_data(buf)) {
+               qc_stream_buf_free(s, &stream_buf);
 
-       /* notify MUX about available buffers. */
-       --qc->stream_buf_count;
-       if (qc->mux_state == QC_MUX_READY) {
-               if (qc->qcc->flags & QC_CF_CONN_FULL) {
-                       qc->qcc->flags &= ~QC_CF_CONN_FULL;
-                       tasklet_wakeup(qc->qcc->wait_event.tasklet);
+               /* Free stream instance if already released and no buffers left. */
+               if (s->release && LIST_ISEMPTY(&s->buf_list)) {
+                       qc_stream_desc_free(s, 0);
+                       *stream = NULL;
                }
        }
 
-       /* Free stream instance if already released and no buffers left. */
-       if (s->release && LIST_ISEMPTY(&s->buf_list)) {
-               qc_stream_desc_free(s, 0);
-               *stream = NULL;
-       }
-
        return diff;
 }