From f8f527b16db5d6cf17f6a986aff710bdd7e48cad Mon Sep 17 00:00:00 2001 From: Stanislaw Gruszka Date: Tue, 30 Apr 2019 10:10:49 +0200 Subject: [PATCH] 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 Signed-off-by: Felix Fietkau --- drivers/net/wireless/mediatek/mt76/usb.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/net/wireless/mediatek/mt76/usb.c b/drivers/net/wireless/mediatek/mt76/usb.c index c299c6591072..bbaa1365bbda 100644 --- a/drivers/net/wireless/mediatek/mt76/usb.c +++ b/drivers/net/wireless/mediatek/mt76/usb.c @@ -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)