[PATCH net-next 3/8] s390/qeth: unify transmit code

Julian Wiedmann
2018-11-08T14:06:17Z

Since commit 82bf5c0867f6 ("s390/qeth: add support for IPv6 TSO"),
qeth_xmit() also knows how to build TSO packets and is practically
identical to qeth_l3_xmit().
Convert qeth_l3_xmit() into a thin wrapper that merely strips the
L2 header off a packet, and calls qeth_xmit() for the actual
TX processing.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
---
drivers/s390/net/qeth_core.h | 8 -----
drivers/s390/net/qeth_core_main.c | 22 ++++++------
drivers/s390/net/qeth_l3_main.c | 72 +++++----------------------------------
3 files changed, 19 insertions(+), 83 deletions(-)

diff --git a/drivers/s390/net/qeth_core.h b/drivers/s390/net/qeth_core.h
index d50d91219cf3..afe3662a4ad5 100644
--- a/drivers/s390/net/qeth_core.h
+++ b/drivers/s390/net/qeth_core.h
@@ -1024,9 +1024,6 @@ int qeth_send_control_data(struct qeth_card *, int, struct qeth_cmd_buffer *,
int (*reply_cb)(struct qeth_card *, struct qeth_reply*, unsigned long),
void *reply_param);
unsigned int qeth_count_elements(struct sk_buff *skb, unsigned int data_offset);
-int qeth_do_send_packet_fast(struct qeth_qdio_out_q *queue, struct sk_buff *skb,
- struct qeth_hdr *hdr, unsigned int offset,
- unsigned int hd_len);
int qeth_do_send_packet(struct qeth_card *card, struct qeth_qdio_out_q *queue,
struct sk_buff *skb, struct qeth_hdr *hdr,
unsigned int offset, unsigned int hd_len,
@@ -1057,11 +1054,6 @@ netdev_features_t qeth_features_check(struct sk_buff *skb,
struct net_device *dev,
netdev_features_t features);
int qeth_vm_request_mac(struct qeth_card *card);
-int qeth_add_hw_header(struct qeth_card *card, struct sk_buff *skb,
- struct qeth_hdr **hdr, unsigned int hdr_len,
- unsigned int proto_len, unsigned int *elements);
-void qeth_fill_tso_ext(struct qeth_hdr_tso *hdr, unsigned int payload_len,
- struct sk_buff *skb, unsigned int proto_len);
int qeth_xmit(struct qeth_card *card, struct sk_buff *skb,
struct qeth_qdio_out_q *queue, int ipv, int cast_type,
void (*fill_header)(struct qeth_card *card, struct qeth_hdr *hdr,
diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index abeecffb6d2e..2568ddc1bbc3 100644
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -3777,9 +3777,9 @@ EXPORT_SYMBOL_GPL(qeth_count_elements);
* The number of needed buffer elements is returned in @elements.
* Error to create the hdr is indicated by returning with < 0.
*/
-int qeth_add_hw_header(struct qeth_card *card, struct sk_buff *skb,
- struct qeth_hdr **hdr, unsigned int hdr_len,
- unsigned int proto_len, unsigned int *elements)
+static int qeth_add_hw_header(struct qeth_card *card, struct sk_buff *skb,
+ struct qeth_hdr **hdr, unsigned int hdr_len,
+ unsigned int proto_len, unsigned int *elements)
{
const unsigned int max_elements = QETH_MAX_BUFFER_ELEMENTS(card);
const unsigned int contiguous = proto_len ? proto_len : 1;
@@ -3849,7 +3849,6 @@ int qeth_add_hw_header(struct qeth_card *card, struct sk_buff *skb,
skb_copy_from_linear_data(skb, ((char *)*hdr) + hdr_len, proto_len);
return 0;
}
-EXPORT_SYMBOL_GPL(qeth_add_hw_header);

static void __qeth_fill_buffer(struct sk_buff *skb,
struct qeth_qdio_out_buffer *buf,
@@ -3972,9 +3971,9 @@ static int qeth_fill_buffer(struct qeth_qdio_out_q *queue,
return flush_cnt;
}

-int qeth_do_send_packet_fast(struct qeth_qdio_out_q *queue, struct sk_buff *skb,
- struct qeth_hdr *hdr, unsigned int offset,
- unsigned int hd_len)
+static int qeth_do_send_packet_fast(struct qeth_qdio_out_q *queue,
+ struct sk_buff *skb, struct qeth_hdr *hdr,
+ unsigned int offset, unsigned int hd_len)
{
int index = queue->next_buf_to_fill;
struct qeth_qdio_out_buffer *buffer = queue->bufs[index];
@@ -3990,7 +3989,6 @@ int qeth_do_send_packet_fast(struct qeth_qdio_out_q *queue, struct sk_buff *skb,
qeth_flush_buffers(queue, index, 1);
return 0;
}
-EXPORT_SYMBOL_GPL(qeth_do_send_packet_fast);

int qeth_do_send_packet(struct qeth_card *card, struct qeth_qdio_out_q *queue,
struct sk_buff *skb, struct qeth_hdr *hdr,
@@ -4082,8 +4080,9 @@ int qeth_do_send_packet(struct qeth_card *card, struct qeth_qdio_out_q *queue,
}
EXPORT_SYMBOL_GPL(qeth_do_send_packet);

-void qeth_fill_tso_ext(struct qeth_hdr_tso *hdr, unsigned int payload_len,
- struct sk_buff *skb, unsigned int proto_len)
+static void qeth_fill_tso_ext(struct qeth_hdr_tso *hdr,
+ unsigned int payload_len, struct sk_buff *skb,
+ unsigned int proto_len)
{
struct qeth_hdr_ext_tso *ext = &hdr->ext;

@@ -4096,7 +4095,6 @@ void qeth_fill_tso_ext(struct qeth_hdr_tso *hdr, unsigned int payload_len,
ext->mss = skb_shinfo(skb)->gso_size;
ext->dg_hdr_len = proto_len;
}
-EXPORT_SYMBOL_GPL(qeth_fill_tso_ext);

int qeth_xmit(struct qeth_card *card, struct sk_buff *skb,
struct qeth_qdio_out_q *queue, int ipv, int cast_type,
@@ -4119,7 +4117,7 @@ int qeth_xmit(struct qeth_card *card, struct sk_buff *skb,
proto_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
} else {
hw_hdr_len = sizeof(struct qeth_hdr);
- proto_len = IS_IQD(card) ? ETH_HLEN : 0;
+ proto_len = (IS_IQD(card) && IS_LAYER2(card)) ? ETH_HLEN : 0;
}

rc = skb_cow_head(skb, hw_hdr_len);
diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c
index 004085344e85..61d847d41cab 100644
--- a/drivers/s390/net/qeth_l3_main.c
+++ b/drivers/s390/net/qeth_l3_main.c
@@ -2036,79 +2036,25 @@ static void qeth_l3_fixup_headers(struct sk_buff *skb)
static int qeth_l3_xmit(struct qeth_card *card, struct sk_buff *skb,
struct qeth_qdio_out_q *queue, int ipv, int cast_type)
{
- unsigned int hw_hdr_len, proto_len, frame_len, elements;
unsigned char eth_hdr[ETH_HLEN];
- bool is_tso = skb_is_gso(skb);
- unsigned int data_offset = 0;
- struct qeth_hdr *hdr = NULL;
- unsigned int hd_len = 0;
- int push_len, rc;
- bool is_sg;
-
- if (is_tso) {
- hw_hdr_len = sizeof(struct qeth_hdr_tso);
- proto_len = skb_transport_offset(skb) + tcp_hdrlen(skb) -
- ETH_HLEN;
- } else {
- hw_hdr_len = sizeof(struct qeth_hdr);
- proto_len = 0;
- }
+ unsigned int hw_hdr_len;
+ int rc;

/* re-use the L2 header area for the HW header: */
+ hw_hdr_len = skb_is_gso(skb) ? sizeof(struct qeth_hdr_tso) :
+ sizeof(struct qeth_hdr);
rc = skb_cow_head(skb, hw_hdr_len - ETH_HLEN);
if (rc)
return rc;
skb_copy_from_linear_data(skb, eth_hdr, ETH_HLEN);
skb_pull(skb, ETH_HLEN);
- frame_len = skb->len;

qeth_l3_fixup_headers(skb);
- push_len = qeth_add_hw_header(card, skb, &hdr, hw_hdr_len, proto_len,
- &elements);
- if (push_len < 0)
- return push_len;
- if (is_tso || !push_len) {
- /* HW header needs its own buffer element. */
- hd_len = hw_hdr_len + proto_len;
- data_offset = push_len + proto_len;
- }
- memset(hdr, 0, hw_hdr_len);
-
- qeth_l3_fill_header(card, hdr, skb, ipv, cast_type, frame_len);
- if (is_tso)
- qeth_fill_tso_ext((struct qeth_hdr_tso *) hdr,
- frame_len - proto_len, skb, proto_len);
-
- is_sg = skb_is_nonlinear(skb);
- if (IS_IQD(card)) {
- rc = qeth_do_send_packet_fast(queue, skb, hdr, data_offset,
- hd_len);
- } else {
- /* TODO: drop skb_orphan() once TX completion is fast enough */
- skb_orphan(skb);
- rc = qeth_do_send_packet(card, queue, skb, hdr, data_offset,
- hd_len, elements);
- }
-
- if (!rc) {
- if (card->options.performance_stats) {
- card->perf_stats.buf_elements_sent += elements;
- if (is_sg)
- card->perf_stats.sg_skbs_sent++;
- if (is_tso) {
- card->perf_stats.large_send_bytes += frame_len;
- card->perf_stats.large_send_cnt++;
- }
- }
- } else {
- if (!push_len)
- kmem_cache_free(qeth_core_header_cache, hdr);
- if (rc == -EBUSY) {
- /* roll back to ETH header */
- skb_pull(skb, push_len);
- skb_push(skb, ETH_HLEN);
- skb_copy_to_linear_data(skb, eth_hdr, ETH_HLEN);
- }
+ rc = qeth_xmit(card, skb, queue, ipv, cast_type, qeth_l3_fill_header);
+ if (rc == -EBUSY) {
+ /* roll back to ETH header */
+ skb_push(skb, ETH_HLEN);
+ skb_copy_to_linear_data(skb, eth_hdr, ETH_HLEN);
}
return rc;
}
--
2.16.4