[PATCH 1/3 v2] dl2k: Handle memory allocation errors in alloc_list

Ondrej Zary
2015-11-18T21:37:17Z

If memory allocation fails in alloc_list(), free the already allocated
memory and return -ENOMEM. In rio_open(), call alloc_list() first and
abort if it fails. Move HW access (set RFDListPtr) out ot alloc_list().

Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
---
drivers/net/ethernet/dlink/dl2k.c | 182 ++++++++++++++++++++-----------------
1 file changed, 97 insertions(+), 85 deletions(-)

diff --git a/drivers/net/ethernet/dlink/dl2k.c b/drivers/net/ethernet/dlink/dl2k.c
index ccca479..ec0eb7f 100644
--- a/drivers/net/ethernet/dlink/dl2k.c
+++ b/drivers/net/ethernet/dlink/dl2k.c
@@ -70,7 +70,6 @@ static const int multicast_filter_limit = 0x40;
static int rio_open (struct net_device *dev);
static void rio_timer (unsigned long data);
static void rio_tx_timeout (struct net_device *dev);
-static void alloc_list (struct net_device *dev);
static netdev_tx_t start_xmit (struct sk_buff *skb, struct net_device *dev);
static irqreturn_t rio_interrupt (int irq, void *dev_instance);
static void rio_free_tx (struct net_device *dev, int irq);
@@ -446,6 +445,92 @@ static void rio_set_led_mode(struct net_device *dev)
dw32(ASICCtrl, mode);
}

+static inline dma_addr_t desc_to_dma(struct netdev_desc *desc)
+{
+ return le64_to_cpu(desc->fraginfo) & DMA_BIT_MASK(48);
+}
+
+static void free_list(struct net_device *dev)
+{
+ struct netdev_private *np = netdev_priv(dev);
+ struct sk_buff *skb;
+ int i;
+
+ /* Free all the skbuffs in the queue. */
+ for (i = 0; i < RX_RING_SIZE; i++) {
+ skb = np->rx_skbuff[i];
+ if (skb) {
+ pci_unmap_single(np->pdev, desc_to_dma(&np->rx_ring[i]),
+ skb->len, PCI_DMA_FROMDEVICE);
+ dev_kfree_skb(skb);
+ np->rx_skbuff[i] = NULL;
+ }
+ np->rx_ring[i].status = 0;
+ np->rx_ring[i].fraginfo = 0;
+ }
+ for (i = 0; i < TX_RING_SIZE; i++) {
+ skb = np->tx_skbuff[i];
+ if (skb) {
+ pci_unmap_single(np->pdev, desc_to_dma(&np->tx_ring[i]),
+ skb->len, PCI_DMA_TODEVICE);
+ dev_kfree_skb(skb);
+ np->tx_skbuff[i] = NULL;
+ }
+ }
+}
+
+ /* allocate and initialize Tx and Rx descriptors */
+static int alloc_list(struct net_device *dev)
+{
+ struct netdev_private *np = netdev_priv(dev);
+ int i;
+
+ np->cur_rx = np->cur_tx = 0;
+ np->old_rx = np->old_tx = 0;
+ np->rx_buf_sz = (dev->mtu <= 1500 ? PACKET_SIZE : dev->mtu + 32);
+
+ /* Initialize Tx descriptors, TFDListPtr leaves in start_xmit(). */
+ for (i = 0; i < TX_RING_SIZE; i++) {
+ np->tx_skbuff[i] = NULL;
+ np->tx_ring[i].status = cpu_to_le64(TFDDone);
+ np->tx_ring[i].next_desc = cpu_to_le64(np->tx_ring_dma +
+ ((i + 1) % TX_RING_SIZE) *
+ sizeof(struct netdev_desc));
+ }
+
+ /* Initialize Rx descriptors */
+ for (i = 0; i < RX_RING_SIZE; i++) {
+ np->rx_ring[i].next_desc = cpu_to_le64(np->rx_ring_dma +
+ ((i + 1) % RX_RING_SIZE) *
+ sizeof(struct netdev_desc));
+ np->rx_ring[i].status = 0;
+ np->rx_ring[i].fraginfo = 0;
+ np->rx_skbuff[i] = NULL;
+ }
+
+ /* Allocate the rx buffers */
+ for (i = 0; i < RX_RING_SIZE; i++) {
+ /* Allocated fixed size of skbuff */
+ struct sk_buff *skb;
+
+ skb = netdev_alloc_skb_ip_align(dev, np->rx_buf_sz);
+ np->rx_skbuff[i] = skb;
+ if (!skb) {
+ free_list(dev);
+ return -ENOMEM;
+ }
+
+ /* Rubicon now supports 40 bits of addressing space. */
+ np->rx_ring[i].fraginfo =
+ cpu_to_le64(pci_map_single(
+ np->pdev, skb->data, np->rx_buf_sz,
+ PCI_DMA_FROMDEVICE));
+ np->rx_ring[i].fraginfo |= cpu_to_le64((u64)np->rx_buf_sz << 48);
+ }
+
+ return 0;
+}
+
static int
rio_open (struct net_device *dev)
{
@@ -455,10 +540,16 @@ rio_open (struct net_device *dev)
int i;
u16 macctrl;

- i = request_irq(irq, rio_interrupt, IRQF_SHARED, dev->name, dev);
+ i = alloc_list(dev);
if (i)
return i;

+ i = request_irq(irq, rio_interrupt, IRQF_SHARED, dev->name, dev);
+ if (i) {
+ free_list(dev);
+ return i;
+ }
+
/* Reset all logic functions */
dw16(ASICCtrl + 2,
GlobalReset | DMAReset | FIFOReset | NetworkReset | HostReset);
@@ -473,7 +564,9 @@ rio_open (struct net_device *dev)
if (np->jumbo != 0)
dw16(MaxFrameSize, MAX_JUMBO+14);

- alloc_list (dev);
+ /* Set RFDListPtr */
+ dw32(RFDListPtr0, np->rx_ring_dma);
+ dw32(RFDListPtr1, 0);

/* Set station address */
/* 16 or 32-bit access is required by TC9020 datasheet but 8-bit works
@@ -586,60 +679,6 @@ rio_tx_timeout (struct net_device *dev)
dev->trans_start = jiffies; /* prevent tx timeout */
}

- /* allocate and initialize Tx and Rx descriptors */
-static void
-alloc_list (struct net_device *dev)
-{
- struct netdev_private *np = netdev_priv(dev);
- void __iomem *ioaddr = np->ioaddr;
- int i;
-
- np->cur_rx = np->cur_tx = 0;
- np->old_rx = np->old_tx = 0;
- np->rx_buf_sz = (dev->mtu <= 1500 ? PACKET_SIZE : dev->mtu + 32);
-
- /* Initialize Tx descriptors, TFDListPtr leaves in start_xmit(). */
- for (i = 0; i < TX_RING_SIZE; i++) {
- np->tx_skbuff[i] = NULL;
- np->tx_ring[i].status = cpu_to_le64 (TFDDone);
- np->tx_ring[i].next_desc = cpu_to_le64 (np->tx_ring_dma +
- ((i+1)%TX_RING_SIZE) *
- sizeof (struct netdev_desc));
- }
-
- /* Initialize Rx descriptors */
- for (i = 0; i < RX_RING_SIZE; i++) {
- np->rx_ring[i].next_desc = cpu_to_le64 (np->rx_ring_dma +
- ((i + 1) % RX_RING_SIZE) *
- sizeof (struct netdev_desc));
- np->rx_ring[i].status = 0;
- np->rx_ring[i].fraginfo = 0;
- np->rx_skbuff[i] = NULL;
- }
-
- /* Allocate the rx buffers */
- for (i = 0; i < RX_RING_SIZE; i++) {
- /* Allocated fixed size of skbuff */
- struct sk_buff *skb;
-
- skb = netdev_alloc_skb_ip_align(dev, np->rx_buf_sz);
- np->rx_skbuff[i] = skb;
- if (skb == NULL)
- break;
-
- /* Rubicon now supports 40 bits of addressing space. */
- np->rx_ring[i].fraginfo =
- cpu_to_le64 ( pci_map_single (
- np->pdev, skb->data, np->rx_buf_sz,
- PCI_DMA_FROMDEVICE));
- np->rx_ring[i].fraginfo |= cpu_to_le64((u64)np->rx_buf_sz << 48);
- }
-
- /* Set RFDListPtr */
- dw32(RFDListPtr0, np->rx_ring_dma);
- dw32(RFDListPtr1, 0);
-}
-
static netdev_tx_t
start_xmit (struct sk_buff *skb, struct net_device *dev)
{
@@ -748,11 +787,6 @@ rio_interrupt (int irq, void *dev_instance)
return IRQ_RETVAL(handled);
}

-static inline dma_addr_t desc_to_dma(struct netdev_desc *desc)
-{
- return le64_to_cpu(desc->fraginfo) & DMA_BIT_MASK(48);
-}
-
static void
rio_free_tx (struct net_device *dev, int irq)
{
@@ -1733,8 +1767,6 @@ rio_close (struct net_device *dev)
void __iomem *ioaddr = np->ioaddr;

struct pci_dev *pdev = np->pdev;
- struct sk_buff *skb;
- int i;

netif_stop_queue (dev);

@@ -1747,27 +1779,7 @@ rio_close (struct net_device *dev)
free_irq(pdev->irq, dev);
del_timer_sync (&np->timer);

- /* Free all the skbuffs in the queue. */
- for (i = 0; i < RX_RING_SIZE; i++) {
- skb = np->rx_skbuff[i];
- if (skb) {
- pci_unmap_single(pdev, desc_to_dma(&np->rx_ring[i]),
- skb->len, PCI_DMA_FROMDEVICE);
- dev_kfree_skb (skb);
- np->rx_skbuff[i] = NULL;
- }
- np->rx_ring[i].status = 0;
- np->rx_ring[i].fraginfo = 0;
- }
- for (i = 0; i < TX_RING_SIZE; i++) {
- skb = np->tx_skbuff[i];
- if (skb) {
- pci_unmap_single(pdev, desc_to_dma(&np->tx_ring[i]),
- skb->len, PCI_DMA_TODEVICE);
- dev_kfree_skb (skb);
- np->tx_skbuff[i] = NULL;