}
EXPORT_SYMBOL_GPL(qeth_get_elements_for_frags);
+static unsigned int qeth_count_elements(struct sk_buff *skb, int data_offset)
+{
+ unsigned int elements = qeth_get_elements_for_frags(skb);
+ addr_t end = (addr_t)skb->data + skb_headlen(skb);
+ addr_t start = (addr_t)skb->data + data_offset;
+
+ if (start != end)
+ elements += qeth_get_elements_for_range(start, end);
+ return elements;
+}
+
/**
* qeth_get_elements_no() - find number of SBALEs for skb data, inc. frags.
* @card: qeth card structure, to check max. elems.
int qeth_get_elements_no(struct qeth_card *card,
struct sk_buff *skb, int extra_elems, int data_offset)
{
- addr_t end = (addr_t)skb->data + skb_headlen(skb);
- int elements = qeth_get_elements_for_frags(skb);
- addr_t start = (addr_t)skb->data + data_offset;
-
- if (start != end)
- elements += qeth_get_elements_for_range(start, end);
+ int elements = qeth_count_elements(skb, data_offset);
if ((elements + extra_elems) > QETH_MAX_BUFFER_ELEMENTS(card)) {
QETH_DBF_MESSAGE(2, "Invalid size of IP packet "
EXPORT_SYMBOL_GPL(qeth_hdr_chk_and_bounce);
/**
- * qeth_push_hdr() - push a qeth_hdr onto an skb.
- * @skb: skb that the qeth_hdr should be pushed onto.
+ * qeth_add_hw_header() - add a HW header to an skb.
+ * @skb: skb that the HW header should be added to.
* @hdr: double pointer to a qeth_hdr. When returning with >= 0,
* it contains a valid pointer to a qeth_hdr.
- * @len: length of the hdr that needs to be pushed on.
+ * @len: length of the HW header.
*
* Returns the pushed length. If the header can't be pushed on
* (eg. because it would cross a page boundary), it is allocated from
* the cache instead and 0 is returned.
+ * The number of needed buffer elements is returned in @elements.
* Error to create the hdr is indicated by returning with < 0.
*/
-int qeth_push_hdr(struct sk_buff *skb, struct qeth_hdr **hdr, unsigned int len)
-{
- if (skb_headroom(skb) >= len &&
- qeth_get_elements_for_range((addr_t)skb->data - len,
- (addr_t)skb->data) == 1) {
+int qeth_add_hw_header(struct qeth_card *card, struct sk_buff *skb,
+ struct qeth_hdr **hdr, unsigned int len,
+ unsigned int *elements)
+{
+ const unsigned int max_elements = QETH_MAX_BUFFER_ELEMENTS(card);
+ unsigned int __elements;
+ addr_t start, end;
+ bool push_ok;
+ int rc;
+
+check_layout:
+ start = (addr_t)skb->data - len;
+ end = (addr_t)skb->data;
+
+ if (qeth_get_elements_for_range(start, end + 1) == 1) {
+ /* Push HW header into same page as first protocol header. */
+ push_ok = true;
+ __elements = qeth_count_elements(skb, 0);
+ } else {
+ __elements = 1 + qeth_count_elements(skb, 0);
+ if (qeth_get_elements_for_range(start, end) == 1)
+ /* Push HW header into a new page. */
+ push_ok = true;
+ else
+ /* Use header cache. */
+ push_ok = false;
+ }
+
+ /* Compress skb to fit into one IO buffer: */
+ if (__elements > max_elements) {
+ if (!skb_is_nonlinear(skb)) {
+ /* Drop it, no easy way of shrinking it further. */
+ QETH_DBF_MESSAGE(2, "Dropped an oversized skb (Max Elements=%u / Actual=%u / Length=%u).\n",
+ max_elements, __elements, skb->len);
+ return -E2BIG;
+ }
+
+ rc = skb_linearize(skb);
+ if (card->options.performance_stats) {
+ if (rc)
+ card->perf_stats.tx_linfail++;
+ else
+ card->perf_stats.tx_lin++;
+ }
+ if (rc)
+ return rc;
+
+ /* Linearization changed the layout, re-evaluate: */
+ goto check_layout;
+ }
+
+ *elements = __elements;
+ /* Add the header: */
+ if (push_ok) {
*hdr = skb_push(skb, len);
return len;
}
return -ENOMEM;
return 0;
}
-EXPORT_SYMBOL_GPL(qeth_push_hdr);
+EXPORT_SYMBOL_GPL(qeth_add_hw_header);
static void __qeth_fill_buffer(struct sk_buff *skb,
struct qeth_qdio_out_buffer *buf,
int ipv)
{
int push_len = sizeof(struct qeth_hdr);
- unsigned int hdr_elements = 0;
struct qeth_hdr *hdr = NULL;
unsigned int hd_len = 0;
unsigned int elements;
bool is_sg;
int rc;
- /* fix hardware limitation: as long as we do not have sbal
- * chaining we can not send long frag lists
- */
- if (!qeth_get_elements_no(card, skb, 0, 0)) {
- rc = skb_linearize(skb);
-
- if (card->options.performance_stats) {
- if (rc)
- card->perf_stats.tx_linfail++;
- else
- card->perf_stats.tx_lin++;
- }
- if (rc)
- return rc;
- }
-
rc = skb_cow_head(skb, push_len);
if (rc)
return rc;
- push_len = qeth_push_hdr(skb, &hdr, push_len);
+ push_len = qeth_add_hw_header(card, skb, &hdr, push_len, &elements);
if (push_len < 0)
return push_len;
if (!push_len) {
/* hdr was allocated from cache */
hd_len = sizeof(*hdr);
- hdr_elements = 1;
}
qeth_l2_fill_header(hdr, skb, cast_type, skb->len - push_len);
if (skb->ip_summed == CHECKSUM_PARTIAL) {
card->perf_stats.tx_csum++;
}
- elements = qeth_get_elements_no(card, skb, hdr_elements, 0);
- if (!elements) {
- rc = -E2BIG;
- goto out;
- }
- elements += hdr_elements;
-
is_sg = skb_is_nonlinear(skb);
/* TODO: remove the skb_orphan() once TX completion is fast enough */
skb_orphan(skb);
rc = qeth_do_send_packet(card, queue, skb, hdr, 0, hd_len, elements);
-out:
+
if (!rc) {
if (card->options.performance_stats) {
card->perf_stats.buf_elements_sent += elements;
int cast_type)
{
const unsigned int hw_hdr_len = sizeof(struct qeth_hdr);
+ unsigned int frame_len, elements;
unsigned char eth_hdr[ETH_HLEN];
- unsigned int hdr_elements = 0;
struct qeth_hdr *hdr = NULL;
- int elements, push_len, rc;
unsigned int hd_len = 0;
- unsigned int frame_len;
+ int push_len, rc;
bool is_sg;
- /* compress skb to fit into one IO buffer: */
- if (!qeth_get_elements_no(card, skb, 0, 0)) {
- rc = skb_linearize(skb);
-
- if (card->options.performance_stats) {
- if (rc)
- card->perf_stats.tx_linfail++;
- else
- card->perf_stats.tx_lin++;
- }
- if (rc)
- return rc;
- }
-
/* re-use the L2 header area for the HW header: */
rc = skb_cow_head(skb, hw_hdr_len - ETH_HLEN);
if (rc)
skb_pull(skb, ETH_HLEN);
frame_len = skb->len;
- push_len = qeth_push_hdr(skb, &hdr, hw_hdr_len);
+ push_len = qeth_add_hw_header(card, skb, &hdr, hw_hdr_len, &elements);
if (push_len < 0)
return push_len;
if (!push_len) {
/* hdr was added discontiguous from skb->data */
hd_len = hw_hdr_len;
- hdr_elements = 1;
}
- elements = qeth_get_elements_no(card, skb, hdr_elements, 0);
- if (!elements) {
- rc = -E2BIG;
- goto out;
- }
- elements += hdr_elements;
-
if (skb->protocol == htons(ETH_P_AF_IUCV))
qeth_l3_fill_af_iucv_hdr(hdr, skb, frame_len);
else
rc = qeth_do_send_packet(card, queue, skb, hdr, 0, hd_len,
elements);
}
-out:
+
if (!rc) {
if (card->options.performance_stats) {
card->perf_stats.buf_elements_sent += elements;
projects / users / hch / configfs.git / commitdiff