From c78e317701a70118a4c8718ebf7a51894f7a65f8 Mon Sep 17 00:00:00 2001 From: Lorenzo Bianconi Date: Mon, 3 Dec 2018 15:34:24 +0100 Subject: [PATCH] mt76: dma: do not build skb if reported len does not fit in buf_size Precompute data length in order to avoid to allocate the related skb data structure if reported length does not fit in queue buf_size Signed-off-by: Lorenzo Bianconi --- dma.c | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) diff --git a/dma.c b/dma.c index b7fd2e11..1db163c4 100644 --- a/dma.c +++ b/dma.c @@ -417,10 +417,9 @@ mt76_add_fragment(struct mt76_dev *dev, struct mt76_queue *q, void *data, static int mt76_dma_rx_process(struct mt76_dev *dev, struct mt76_queue *q, int budget) { + int len, data_len, done = 0; struct sk_buff *skb; unsigned char *data; - int len; - int done = 0; bool more; while (done < budget) { @@ -430,7 +429,12 @@ mt76_dma_rx_process(struct mt76_dev *dev, struct mt76_queue *q, int budget) if (!data) break; - if (q->buf_size < len + q->buf_offset) { + if (q->rx_head) + data_len = q->buf_size; + else + data_len = SKB_WITH_OVERHEAD(q->buf_size); + + if (data_len < len + q->buf_offset) { dev_kfree_skb(q->rx_head); q->rx_head = NULL; @@ -448,12 +452,7 @@ mt76_dma_rx_process(struct mt76_dev *dev, struct mt76_queue *q, int budget) skb_free_frag(data); continue; } - skb_reserve(skb, q->buf_offset); - if (skb->tail + len > skb->end) { - dev_kfree_skb(skb); - continue; - } if (q == &dev->q_rx[MT_RXQ_MCU]) { u32 *rxfce = (u32 *) skb->cb;