target/linux/mediatek/patches-4.4/0083-net-next-mediatek-fix-missing-free-of-scratch-memory.patch

   1 From b48745c534ced06005d2ba57198b54a6a160b39d Mon Sep 17 00:00:00 2001
   2 From: John Crispin <john@phrozen.org>
   3 Date: Sat, 23 Apr 2016 09:18:28 +0200
   4 Subject: [PATCH 083/102] net-next: mediatek: fix missing free of scratch
   5  memory
   6
   7 Scratch memory gets allocated in mtk_init_fq_dma() but the corresponding
   8 code to free it is missing inside mtk_dma_free() causing a memory leak.
   9 With this patch applied, we can run ifconfig/up/down several thousand
  10 times without any problems.
  11
  12 Signed-off-by: John Crispin <john@phrozen.org>
  13 ---
  14  drivers/net/ethernet/mediatek/mtk_eth_soc.c |   18 +++++++++++++-----
  15  drivers/net/ethernet/mediatek/mtk_eth_soc.h |    2 ++
  16  2 files changed, 15 insertions(+), 5 deletions(-)
  17
  18 --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
  19 +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
  20 @@ -484,14 +484,14 @@ static inline void mtk_rx_get_desc(struc
  21  /* the qdma core needs scratch memory to be setup */
  22  static int mtk_init_fq_dma(struct mtk_eth *eth)
  23  {
  24 -       dma_addr_t phy_ring_head, phy_ring_tail;
  25 +       dma_addr_t phy_ring_tail;
  26         int cnt = MTK_DMA_SIZE;
  27         dma_addr_t dma_addr;
  28         int i;
  29
  30         eth->scratch_ring = dma_alloc_coherent(eth->dev,
  31                                                cnt * sizeof(struct mtk_tx_dma),
  32 -                                              &phy_ring_head,
  33 +                                              &eth->phy_scratch_ring,
  34                                                GFP_ATOMIC | __GFP_ZERO);
  35         if (unlikely(!eth->scratch_ring))
  36                 return -ENOMEM;
  37 @@ -508,19 +508,19 @@ static int mtk_init_fq_dma(struct mtk_et
  38                 return -ENOMEM;
  39
  40         memset(eth->scratch_ring, 0x0, sizeof(struct mtk_tx_dma) * cnt);
  41 -       phy_ring_tail = phy_ring_head +
  42 +       phy_ring_tail = eth->phy_scratch_ring +
  43                         (sizeof(struct mtk_tx_dma) * (cnt - 1));
  44
  45         for (i = 0; i < cnt; i++) {
  46                 eth->scratch_ring[i].txd1 =
  47                                         (dma_addr + (i * MTK_QDMA_PAGE_SIZE));
  48                 if (i < cnt - 1)
  49 -                       eth->scratch_ring[i].txd2 = (phy_ring_head +
  50 +                       eth->scratch_ring[i].txd2 = (eth->phy_scratch_ring +
  51                                 ((i + 1) * sizeof(struct mtk_tx_dma)));
  52                 eth->scratch_ring[i].txd3 = TX_DMA_SDL(MTK_QDMA_PAGE_SIZE);
  53         }
  54
  55 -       mtk_w32(eth, phy_ring_head, MTK_QDMA_FQ_HEAD);
  56 +       mtk_w32(eth, eth->phy_scratch_ring, MTK_QDMA_FQ_HEAD);
  57         mtk_w32(eth, phy_ring_tail, MTK_QDMA_FQ_TAIL);
  58         mtk_w32(eth, (cnt << 16) | cnt, MTK_QDMA_FQ_CNT);
  59         mtk_w32(eth, MTK_QDMA_PAGE_SIZE << 16, MTK_QDMA_FQ_BLEN);
  60 @@ -1220,6 +1220,14 @@ static void mtk_dma_free(struct mtk_eth
  61         for (i = 0; i < MTK_MAC_COUNT; i++)
  62                 if (eth->netdev[i])
  63                         netdev_reset_queue(eth->netdev[i]);
  64 +       if (eth->scratch_ring) {
  65 +               dma_free_coherent(eth->dev,
  66 +                                 MTK_DMA_SIZE * sizeof(struct mtk_tx_dma),
  67 +                                 eth->scratch_ring,
  68 +                                 eth->phy_scratch_ring);
  69 +               eth->scratch_ring = NULL;
  70 +               eth->phy_scratch_ring = 0;
  71 +       }
  72         mtk_tx_clean(eth);
  73         mtk_rx_clean(eth);
  74         kfree(eth->scratch_head);
  75 --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.h
  76 +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
  77 @@ -357,6 +357,7 @@ struct mtk_rx_ring {
  78   * @rx_ring:           Pointer to the memore holding info about the RX ring
  79   * @rx_napi:           The NAPI struct
  80   * @scratch_ring:      Newer SoCs need memory for a second HW managed TX ring
  81 + * @phy_scratch_ring:  physical address of scratch_ring
  82   * @scratch_head:      The scratch memory that scratch_ring points to.
  83   * @clk_ethif:         The ethif clock
  84   * @clk_esw:           The switch clock
  85 @@ -384,6 +385,7 @@ struct mtk_eth {
  86         struct mtk_rx_ring              rx_ring;
  87         struct napi_struct              rx_napi;
  88         struct mtk_tx_dma               *scratch_ring;
  89 +       dma_addr_t                      phy_scratch_ring;
  90         void                            *scratch_head;
  91         struct clk                      *clk_ethif;
  92         struct clk                      *clk_esw;