From f8f527b16db5d6cf17f6a986aff710bdd7e48cad Mon Sep 17 00:00:00 2001
From: Stanislaw Gruszka <sgruszka@redhat.com>
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 <sgruszka@redhat.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
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 c299c65910724..bbaa1365bbda2 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)
--
2.30.2