mt76: usb: use EP max packet aligned buffer sizes for rx

If buffer size is not usb_endpoint_maxp (512 or 1024 bytes) multiple,
usb host driver has to use bounce buffer and copy data. For RX we can
avoid that since we alreay allocate q->buf_size (2kB) buffers and
mt76usb hardware will not fill more data as rx packet size is limited
by network protocol. However add error message if this assumption
somehow will be not true.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
This commit is contained in:
Stanislaw Gruszka 2019-04-30 10:10:49 +02:00 committed by Felix Fietkau
parent 4d0fe26f7c
commit f8f527b16d
1 changed files with 6 additions and 5 deletions

View File

@ -286,7 +286,6 @@ static int
mt76u_fill_rx_sg(struct mt76_dev *dev, struct mt76_queue *q, struct urb *urb,
int nsgs, gfp_t gfp)
{
int sglen = SKB_WITH_OVERHEAD(q->buf_size);
int i;
for (i = 0; i < nsgs; i++) {
@ -300,7 +299,7 @@ mt76u_fill_rx_sg(struct mt76_dev *dev, struct mt76_queue *q, struct urb *urb,
page = virt_to_head_page(data);
offset = data - page_address(page);
sg_set_page(&urb->sg[i], page, sglen, offset);
sg_set_page(&urb->sg[i], page, q->buf_size, offset);
}
if (i < nsgs) {
@ -312,7 +311,7 @@ mt76u_fill_rx_sg(struct mt76_dev *dev, struct mt76_queue *q, struct urb *urb,
}
urb->num_sgs = max_t(int, i, urb->num_sgs);
urb->transfer_buffer_length = urb->num_sgs * sglen,
urb->transfer_buffer_length = urb->num_sgs * q->buf_size,
sg_init_marker(urb->sg, urb->num_sgs);
return i ? : -ENOMEM;
@ -326,7 +325,7 @@ mt76u_refill_rx(struct mt76_dev *dev, struct urb *urb, int nsgs, gfp_t gfp)
if (dev->usb.sg_en) {
return mt76u_fill_rx_sg(dev, q, urb, nsgs, gfp);
} else {
urb->transfer_buffer_length = SKB_WITH_OVERHEAD(q->buf_size);
urb->transfer_buffer_length = q->buf_size;
urb->transfer_buffer = page_frag_alloc(&q->rx_page,
q->buf_size, gfp);
return urb->transfer_buffer ? 0 : -ENOMEM;
@ -447,8 +446,10 @@ mt76u_process_rx_entry(struct mt76_dev *dev, struct urb *urb)
return 0;
data_len = min_t(int, len, data_len - MT_DMA_HDR_LEN);
if (MT_DMA_HDR_LEN + data_len > SKB_WITH_OVERHEAD(q->buf_size))
if (MT_DMA_HDR_LEN + data_len > SKB_WITH_OVERHEAD(q->buf_size)) {
dev_err_ratelimited(dev->dev, "rx data too big %d\n", data_len);
return 0;
}
skb = build_skb(data, q->buf_size);
if (!skb)