stmmac: fix init_dma_desc_rings() to handle errors

In stmmac_init_rx_buffers():
* add missing handling of dma_map_single() error
* remove superfluous unlikely() optimization while at it

Add stmmac_free_rx_buffers() helper and use it in dma_free_rx_skbufs().

In init_dma_desc_rings():
* add missing handling of kmalloc_array() errors
* fix handling of dma_alloc_coherent() and stmmac_init_rx_buffers() errors
* make function return an error value on error and 0 on success

In stmmac_open():
* add handling of init_dma_desc_rings() return value

Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 92 insertions, 19 deletions

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index f2ccb36e8685..0a9bb9d30c3f 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -939,15 +939,20 @@ static int stmmac_init_rx_buffers(struct stmmac_priv *priv, struct dma_desc *p,
 
         skb = __netdev_alloc_skb(priv->dev, priv->dma_buf_sz + NET_IP_ALIGN,
                                  GFP_KERNEL);
-        if (unlikely(skb == NULL)) {
+        if (!skb) {
                 pr_err("%s: Rx init fails; skb is NULL\n", __func__);
-                return 1;
+                return -ENOMEM;
         }
         skb_reserve(skb, NET_IP_ALIGN);
         priv->rx_skbuff[i] = skb;
         priv->rx_skbuff_dma[i] = dma_map_single(priv->device, skb->data,
                                                 priv->dma_buf_sz,
                                                 DMA_FROM_DEVICE);
+        if (dma_mapping_error(priv->device, priv->rx_skbuff_dma[i])) {
+                pr_err("%s: DMA mapping error\n", __func__);
+                dev_kfree_skb_any(skb);
+                return -EINVAL;
+        }
 
         p->des2 = priv->rx_skbuff_dma[i];
 
@@ -958,6 +963,16 @@ static int stmmac_init_rx_buffers(struct stmmac_priv *priv, struct dma_desc *p,
         return 0;
 }
 
+static void stmmac_free_rx_buffers(struct stmmac_priv *priv, int i)
+{
+        if (priv->rx_skbuff[i]) {
+                dma_unmap_single(priv->device, priv->rx_skbuff_dma[i],
+                                 priv->dma_buf_sz, DMA_FROM_DEVICE);
+                dev_kfree_skb_any(priv->rx_skbuff[i]);
+        }
+        priv->rx_skbuff[i] = NULL;
+}
+
 /**
  * init_dma_desc_rings - init the RX/TX descriptor rings
  * @dev: net device structure
@@ -965,13 +980,14 @@ static int stmmac_init_rx_buffers(struct stmmac_priv *priv, struct dma_desc *p,
  * and allocates the socket buffers. It suppors the chained and ring
  * modes.
  */
-static void init_dma_desc_rings(struct net_device *dev)
+static int init_dma_desc_rings(struct net_device *dev)
 {
         int i;
         struct stmmac_priv *priv = netdev_priv(dev);
         unsigned int txsize = priv->dma_tx_size;
         unsigned int rxsize = priv->dma_rx_size;
         unsigned int bfsize = 0;
+        int ret = -ENOMEM;
 
         /* Set the max buffer size according to the DESC mode
          * and the MTU. Note that RING mode allows 16KiB bsize.
@@ -992,34 +1008,60 @@ static void init_dma_desc_rings(struct net_device *dev)
                                                           dma_extended_desc),
                                                    &priv->dma_rx_phy,
                                                    GFP_KERNEL);
+                if (!priv->dma_erx)
+                        goto err_dma;
+
                 priv->dma_etx = dma_alloc_coherent(priv->device, txsize *
                                                    sizeof(struct
                                                           dma_extended_desc),
                                                    &priv->dma_tx_phy,
                                                    GFP_KERNEL);
-                if ((!priv->dma_erx) || (!priv->dma_etx))
-                        return;
+                if (!priv->dma_etx) {
+                        dma_free_coherent(priv->device, priv->dma_rx_size *
+                                        sizeof(struct dma_extended_desc),
+                                        priv->dma_erx, priv->dma_rx_phy);
+                        goto err_dma;
+                }
         } else {
                 priv->dma_rx = dma_alloc_coherent(priv->device, rxsize *
                                                   sizeof(struct dma_desc),
                                                   &priv->dma_rx_phy,
                                                   GFP_KERNEL);
+                if (!priv->dma_rx)
+                        goto err_dma;
+
                 priv->dma_tx = dma_alloc_coherent(priv->device, txsize *
                                                   sizeof(struct dma_desc),
                                                   &priv->dma_tx_phy,
                                                   GFP_KERNEL);
-                if ((!priv->dma_rx) || (!priv->dma_tx))
-                        return;
+                if (!priv->dma_tx) {
+                        dma_free_coherent(priv->device, priv->dma_rx_size *
+                                        sizeof(struct dma_desc),
+                                        priv->dma_rx, priv->dma_rx_phy);
+                        goto err_dma;
+                }
         }
 
         priv->rx_skbuff_dma = kmalloc_array(rxsize, sizeof(dma_addr_t),
                                             GFP_KERNEL);
+        if (!priv->rx_skbuff_dma)
+                goto err_rx_skbuff_dma;
+
         priv->rx_skbuff = kmalloc_array(rxsize, sizeof(struct sk_buff *),
                                         GFP_KERNEL);
+        if (!priv->rx_skbuff)
+                goto err_rx_skbuff;
+
         priv->tx_skbuff_dma = kmalloc_array(txsize, sizeof(dma_addr_t),
                                             GFP_KERNEL);
+        if (!priv->tx_skbuff_dma)
+                goto err_tx_skbuff_dma;
+
         priv->tx_skbuff = kmalloc_array(txsize, sizeof(struct sk_buff *),
                                         GFP_KERNEL);
+        if (!priv->tx_skbuff)
+                goto err_tx_skbuff;
+
         if (netif_msg_probe(priv)) {
                 pr_debug("(%s) dma_rx_phy=0x%08x dma_tx_phy=0x%08x\n", __func__,
                          (u32) priv->dma_rx_phy, (u32) priv->dma_tx_phy);
@@ -1034,8 +1076,9 @@ static void init_dma_desc_rings(struct net_device *dev)
                 else
                         p = priv->dma_rx + i;
 
-                if (stmmac_init_rx_buffers(priv, p, i))
-                        break;
+                ret = stmmac_init_rx_buffers(priv, p, i);
+                if (ret)
+                        goto err_init_rx_buffers;
 
                 if (netif_msg_probe(priv))
                         pr_debug("[%p]\t[%p]\t[%x]\n", priv->rx_skbuff[i],
@@ -1081,20 +1124,44 @@ static void init_dma_desc_rings(struct net_device *dev)
 
         if (netif_msg_hw(priv))
                 stmmac_display_rings(priv);
+
+        return 0;
+err_init_rx_buffers:
+        while (--i >= 0)
+                stmmac_free_rx_buffers(priv, i);
+        kfree(priv->tx_skbuff);
+err_tx_skbuff:
+        kfree(priv->tx_skbuff_dma);
+err_tx_skbuff_dma:
+        kfree(priv->rx_skbuff);
+err_rx_skbuff:
+        kfree(priv->rx_skbuff_dma);
+err_rx_skbuff_dma:
+        if (priv->extend_desc) {
+                dma_free_coherent(priv->device, priv->dma_tx_size *
+                                  sizeof(struct dma_extended_desc),
+                                  priv->dma_etx, priv->dma_tx_phy);
+                dma_free_coherent(priv->device, priv->dma_rx_size *
+                                  sizeof(struct dma_extended_desc),
+                                  priv->dma_erx, priv->dma_rx_phy);
+        } else {
+                dma_free_coherent(priv->device,
+                                priv->dma_tx_size * sizeof(struct dma_desc),
+                                priv->dma_tx, priv->dma_tx_phy);
+                dma_free_coherent(priv->device,
+                                priv->dma_rx_size * sizeof(struct dma_desc),
+                                priv->dma_rx, priv->dma_rx_phy);
+        }
+err_dma:
+        return ret;
 }
 
 static void dma_free_rx_skbufs(struct stmmac_priv *priv)
 {
         int i;
 
-        for (i = 0; i < priv->dma_rx_size; i++) {
-                if (priv->rx_skbuff[i]) {
-                        dma_unmap_single(priv->device, priv->rx_skbuff_dma[i],
-                                         priv->dma_buf_sz, DMA_FROM_DEVICE);
-                        dev_kfree_skb_any(priv->rx_skbuff[i]);
-                }
-                priv->rx_skbuff[i] = NULL;
-        }
+        for (i = 0; i < priv->dma_rx_size; i++)
+                stmmac_free_rx_buffers(priv, i);
 }
 
 static void dma_free_tx_skbufs(struct stmmac_priv *priv)
@@ -1560,12 +1627,17 @@ static int stmmac_open(struct net_device *dev)
         priv->dma_tx_size = STMMAC_ALIGN(dma_txsize);
         priv->dma_rx_size = STMMAC_ALIGN(dma_rxsize);
         priv->dma_buf_sz = STMMAC_ALIGN(buf_sz);
-        init_dma_desc_rings(dev);
+
+        ret = init_dma_desc_rings(dev);
+        if (ret < 0) {
+                pr_err("%s: DMA descriptors initialization failed\n", __func__);
+                goto dma_desc_error;
+        }
 
         /* DMA initialization and SW reset */
         ret = stmmac_init_dma_engine(priv);
         if (ret < 0) {
-                pr_err("%s: DMA initialization failed\n", __func__);
+                pr_err("%s: DMA engine initialization failed\n", __func__);
                 goto init_error;
         }
 
@@ -1672,6 +1744,7 @@ wolirq_error:
 
 init_error:
         free_dma_desc_resources(priv);
+dma_desc_error:
         if (priv->phydev)
                 phy_disconnect(priv->phydev);
 phy_error: