[PATCH net-next 6/7] s390/qeth: unify code to build header elements

Julian Wiedmann
2017-08-18T08:19:09Z

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>
---
drivers/s390/net/qeth_core_main.c | 29 +++++++++++++++--------------
1 file changed, 15 insertions(+), 14 deletions(-)

diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index cef9f54d0eb9..ffefdd97abca 100644
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -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++;
}

--
2.11.2