Re: [PATCH v2] VNIC: Adding support for Cavium ThunderX network controller

From: Andrey Panin
Date: Wed Nov 12 2014 - 10:20:10 EST


On 313, 11 09, 2014 at 09:14:05PM -0800, Robert Richter wrote:

I apologize for possibly repeated mail, my mailsystem was misconfigured :(

Some comments from quick look are below.


> +static int nic_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
> +{
> + struct device *dev = &pdev->dev;
> + struct net_device *netdev;
> + struct nicpf *nic;
> + int err;
> +
> + netdev = alloc_etherdev(sizeof(struct nicpf));
> + if (!netdev)
> + return -ENOMEM;
> +
> + pci_set_drvdata(pdev, netdev);
> +
> + SET_NETDEV_DEV(netdev, &pdev->dev);
> +
> + nic = netdev_priv(netdev);
> + nic->netdev = netdev;
> + nic->pdev = pdev;
> +
> + err = pci_enable_device(pdev);
> + if (err) {
> + dev_err(dev, "Failed to enable PCI device\n");
> + goto exit;

Looks like you leaked netdev here.

> + }
> +
> + err = pci_request_regions(pdev, DRV_NAME);
> + if (err) {
> + dev_err(dev, "PCI request regions failed 0x%x\n", err);
> + goto err_disable_device;
> + }
> +
> + err = pci_set_dma_mask(pdev, DMA_BIT_MASK(48));
> + if (err) {
> + dev_err(dev, "Unable to get usable DMA configuration\n");
> + goto err_release_regions;
> + }
> +
> + err = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(48));
> + if (err) {
> + dev_err(dev, "unable to get 48-bit DMA for consistent allocations\n");
> + goto err_release_regions;
> + }
> +
> + /* MAP PF's configuration registers */
> + nic->reg_base = (uint64_t)pci_ioremap_bar(pdev, PCI_CFG_REG_BAR_NUM);
> + if (!nic->reg_base) {
> + dev_err(dev, "Cannot map config register space, aborting\n");
> + err = -ENOMEM;
> + goto err_release_regions;
> + }
> + nic->node = NIC_NODE_ID(pci_resource_start(pdev, PCI_CFG_REG_BAR_NUM));
> +
> + /* By default set NIC in TNS bypass mode */
> + nic->flags &= ~NIC_TNS_ENABLED;
> + nic_set_lmac_vf_mapping(nic);
> +
> + /* Initialize hardware */
> + nic_init_hw(nic);
> +
> + /* Set RSS TBL size for each VF */
> + nic->rss_ind_tbl_size = max((NIC_RSSI_COUNT / nic->num_vf_en),
> + NIC_MAX_RSS_IDR_TBL_SIZE);
> + nic->rss_ind_tbl_size = rounddown_pow_of_two(nic->rss_ind_tbl_size);
> +
> + /* Register interrupts */
> + if (nic_register_interrupts(nic))
> + goto err_unmap_resources;
> +
> + /* Configure SRIOV */
> + if (!nic_sriov_init(pdev, nic))
> + goto err_unmap_resources;
> +
> + goto exit;

Why not simply return 0; ?

> +
> +err_unmap_resources:
> + if (nic->reg_base)

This check looks unnecessary.

> + iounmap((void *)nic->reg_base);
> +err_release_regions:
> + pci_release_regions(pdev);
> +err_disable_device:
> + pci_disable_device(pdev);
> +exit:
> + return err;
> +}


> +static int bgx_register_interrupts(struct bgx *bgx, uint8_t lmac)
> +{
> + int irq, ret = 0;
> +
> + /* Register only link interrupts now */
> + irq = SPUX_INT + (lmac * BGX_LMAC_VEC_OFFSET);
> + sprintf(bgx->irq_name[irq], "LMAC%d", lmac);
> + ret = request_irq(bgx->msix_entries[irq].vector,
> + bgx_lmac_intr_handler, 0, bgx->irq_name[irq], bgx);
> + if (ret)
> + goto fail;
> + else

This else just hurts readability.

> + bgx->irq_allocated[irq] = 1;
> +
> + /* Enable link interrupt */
> + bgx_enable_link_intr(bgx, lmac);
> + return 0;
> +
> +fail:

The code below copypasted from bgx_unregister_interrupts()
Looks like good candidate for helper function.

> + dev_err(&bgx->pdev->dev, "Request irq failed\n");
> + for (irq = 0; irq < bgx->num_vec; irq++) {
> + if (bgx->irq_allocated[irq])
> + free_irq(bgx->msix_entries[irq].vector, bgx);
> + bgx->irq_allocated[irq] = 0;
> + }
> + return 1;
> +}
> +
> +static void bgx_unregister_interrupts(struct bgx *bgx)
> +{
> + int irq;
> + /* Free registered interrupts */
> + for (irq = 0; irq < bgx->num_vec; irq++) {
> + if (bgx->irq_allocated[irq])
> + free_irq(bgx->msix_entries[irq].vector, bgx);
> + bgx->irq_allocated[irq] = 0;
> + }
> + /* Disable MSI-X */
> + bgx_disable_msix(bgx);
> +}
> +

> +void bgx_lmac_enable(struct bgx *bgx, int8_t lmac)
> +{
> + uint64_t dmac_bcast = (1ULL << 48) - 1;
> +
> + bgx_reg_write(bgx, lmac, BGX_CMRX_CFG,
> + (1 << 15) | (1 << 14) | (1 << 13));
> +
> + /* Register interrupts */
> + bgx_register_interrupts(bgx, lmac);

bgx_register_interrupts() can fail (due to request_irq), but it's return
value is not checked.

> +
> + /* Add broadcast MAC into all LMAC's DMAC filters */
> + for (lmac = 0; lmac < bgx->lmac_count; lmac++)
> + bgx_add_dmac_addr(dmac_bcast, 0, bgx->bgx_id, lmac);
> +}

> +static int bgx_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
> +{
> + struct device *dev = &pdev->dev;
> + struct bgx *bgx;
> + int err;
> + uint8_t lmac = 0;
> +
> + bgx = kzalloc(sizeof(*bgx), GFP_KERNEL);

kzalloc() return value not checked

> + bgx->pdev = pdev;
> +
> + pci_set_drvdata(pdev, bgx);
> +
> + err = pci_enable_device(pdev);
> + if (err) {
> + dev_err(dev, "Failed to enable PCI device\n");
> + goto exit;

bgx is leaked here.

> + }
> +
> + err = pci_request_regions(pdev, DRV_NAME);
> + if (err) {
> + dev_err(dev, "PCI request regions failed 0x%x\n", err);
> + goto err_disable_device;
> + }
> +
> + /* MAP configuration registers */
> + bgx->reg_base = (uint64_t)pci_ioremap_bar(pdev, PCI_CFG_REG_BAR_NUM);
> + if (!bgx->reg_base) {
> + dev_err(dev, "BGX: Cannot map CSR memory space, aborting\n");
> + err = -ENOMEM;
> + goto err_release_regions;
> + }
> + bgx->bgx_id = (pci_resource_start(pdev, PCI_CFG_REG_BAR_NUM) >> 24) & 1;
> + bgx->bgx_id += NODE_ID(pci_resource_start(pdev, PCI_CFG_REG_BAR_NUM))
> + * MAX_BGX_PER_CN88XX;
> + bgx_vnic[bgx->bgx_id] = bgx;
> +
> + /* Initialize BGX hardware */
> + bgx_init_hw(bgx);
> + /* Enable MSI-X */
> + if (!bgx_enable_msix(bgx))
> + return 1;

Massive resource leak here.

> + /* Enable all LMACs */
> + for (lmac = 0; lmac < bgx->lmac_count; lmac++)
> + bgx_lmac_enable(bgx, lmac);

See comment about bgx_lmac_enable() above.

> + goto exit;
> +

Lines below are unreachable.

> + if (bgx->reg_base)
> + iounmap((void *)bgx->reg_base);
> +err_release_regions:
> + pci_release_regions(pdev);
> +err_disable_device:
> + pci_disable_device(pdev);
> +exit:
> + return err;
> +}
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/