s390/qeth: unify code to build header elements
authorJulian Wiedmann <jwi@linux.vnet.ibm.com>
Fri, 18 Aug 2017 08:19:09 +0000 (10:19 +0200)
committerDavid S. Miller <davem@davemloft.net>
Fri, 18 Aug 2017 17:21:30 +0000 (10:21 -0700)
After plenty of refactoring, use hd_len as single indication that
the skb needs a dedicated header element.

This preserves existing behaviour for TSO, as 'hdr' always points
to skb->data.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/s390/net/qeth_core_main.c

index cef9f54d0eb92064b0b2d8fea54f3eff2af68916..ffefdd97abca199d7b05e70df4aa4dc2109311a4 100644 (file)
@@ -3953,37 +3953,38 @@ static void __qeth_fill_buffer(struct sk_buff *skb,
        buf->next_element_to_fill = element;
 }
 
+/**
+ * qeth_fill_buffer() - map skb into an output buffer
+ * @queue:     QDIO queue to submit the buffer on
+ * @buf:       buffer to transport the skb
+ * @skb:       skb to map into the buffer
+ * @hdr:       qeth_hdr for this skb. Either at skb->data, or allocated
+ *             from qeth_core_header_cache.
+ * @offset:    when mapping the skb, start at skb->data + offset
+ * @hd_len:    if > 0, build a dedicated header element of this size
+ */
 static int qeth_fill_buffer(struct qeth_qdio_out_q *queue,
                            struct qeth_qdio_out_buffer *buf,
                            struct sk_buff *skb, struct qeth_hdr *hdr,
                            unsigned int offset, unsigned int hd_len)
 {
-       struct qdio_buffer *buffer;
+       struct qdio_buffer *buffer = buf->buffer;
        bool is_first_elem = true;
        int flush_cnt = 0;
 
-       buffer = buf->buffer;
        refcount_inc(&skb->users);
        skb_queue_tail(&buf->skb_list, skb);
 
-       if (hdr->hdr.l3.id == QETH_HEADER_TYPE_TSO) {
-               int element = buf->next_element_to_fill;
-               is_first_elem = false;
-
-               /*fill first buffer entry only with header information */
-               buffer->element[element].addr = skb->data;
-               buffer->element[element].length = hd_len;
-               buffer->element[element].eflags = SBAL_EFLAGS_FIRST_FRAG;
-               buf->next_element_to_fill++;
-       /* IQD */
-       } else if (offset) {
+       /* build dedicated header element */
+       if (hd_len) {
                int element = buf->next_element_to_fill;
                is_first_elem = false;
 
                buffer->element[element].addr = hdr;
                buffer->element[element].length = hd_len;
                buffer->element[element].eflags = SBAL_EFLAGS_FIRST_FRAG;
-               buf->is_header[element] = 1;
+               /* remember to free cache-allocated qeth_hdr: */
+               buf->is_header[element] = ((void *)hdr != skb->data);
                buf->next_element_to_fill++;
        }