On Tue, Feb 02, 2021 at 05:56:34PM +0100, Gustavo Pimentel wrote:
> Add Synopsys DesignWare xData IP driver. This driver enables/disables
> the PCI traffic generator module pertain to the Synopsys DesignWare
> prototype.
>
> Signed-off-by: Gustavo Pimentel <gustavo.pimentel@xxxxxxxxxxxx>
> ---
> drivers/misc/dw-xdata-pcie.c | 379 +++++++++++++++++++++++++++++++++++++++++++
You are adding sysfs entries but you do not have any Documentation/ABI/
entries for us to be able to properly review this code :(
> +static ssize_t sysfs_write_show(struct kobject *kobj,
> + struct kobj_attribute *attr, char *buf)
> +{
> + struct device *dev = kobj2device(kobj);
> + struct pci_dev *pdev = device2pci_dev(dev);
> + struct dw_xdata *dw = pci_get_drvdata(pdev);
> + u64 rate;
> +
> + dw_xdata_perf(dw, &rate, true);
> + return sprintf(buf, "%llu MB/s\n", rate);
sysfs_emit()
> +}
> +
> +static ssize_t sysfs_write_store(struct kobject *kobj,
> + struct kobj_attribute *attr, const char *buf,
> + size_t count)
> +{
> + struct device *dev = kobj2device(kobj);
> + struct pci_dev *pdev = device2pci_dev(dev);
> + struct dw_xdata *dw = pci_get_drvdata(pdev);
> +
> + pci_dbg(pdev, "xData: requested write transfer\n");
> + dw_xdata_start(dw, true);
> +
> + return count;
> +}
> +
> +struct kobj_attribute sysfs_write_attr = __ATTR(write, 0644,
> + sysfs_write_show,
> + sysfs_write_store);
__ATTR_RW() please
> +
> +static ssize_t sysfs_read_show(struct kobject *kobj,
> + struct kobj_attribute *attr, char *buf)
> +{
> + struct device *dev = kobj2device(kobj);
> + struct pci_dev *pdev = device2pci_dev(dev);
> + struct dw_xdata *dw = pci_get_drvdata(pdev);
> + u64 rate;
> +
> + dw_xdata_perf(dw, &rate, false);
> + return sprintf(buf, "%llu MB/s\n", rate);
sysfs_emit()
> +}
> +
> +static ssize_t sysfs_read_store(struct kobject *kobj,
> + struct kobj_attribute *attr, const char *buf,
> + size_t count)
> +{
> + struct device *dev = kobj2device(kobj);
> + struct pci_dev *pdev = device2pci_dev(dev);
> + struct dw_xdata *dw = pci_get_drvdata(pdev);
> +
> + pci_dbg(pdev, "xData: requested read transfer\n");
> + dw_xdata_start(dw, false);
> +
> + return count;
> +}
> +
> +struct kobj_attribute sysfs_read_attr = __ATTR(read, 0644,
> + sysfs_read_show,
> + sysfs_read_store);
__ATTR_RW()
> +
> +static ssize_t sysfs_stop_store(struct kobject *kobj,
> + struct kobj_attribute *attr, const char *buf,
> + size_t count)
> +{
> + struct device *dev = kobj2device(kobj);
Wait, what???
Why are you creating "raw" kobjects here? This is a device, use device
attributes. Use DEVICE_ATTR_RW() for all of the above.
Who reviewed this thing???
> + struct pci_dev *pdev = device2pci_dev(dev);
> + struct dw_xdata *dw = pci_get_drvdata(pdev);
> +
> + pci_dbg(pdev, "xData: requested stop any transfer\n");
> + dw_xdata_stop(dw);
> +
> + return count;
> +}
> +
> +struct kobj_attribute sysfs_stop_attr = __ATTR(stop, 0644,
> + NULL,
> + sysfs_stop_store);
> +
> +static int dw_xdata_pcie_probe(struct pci_dev *pdev,
> + const struct pci_device_id *pid)
> +{
> + const struct dw_xdata_pcie_data *pdata = (void *)pid->driver_data;
> + struct device *dev = &pdev->dev;
> + struct dw_xdata *dw;
> + u64 addr;
> + int err;
> +
> + /* Enable PCI device */
> + err = pcim_enable_device(pdev);
> + if (err) {
> + pci_err(pdev, "enabling device failed\n");
> + return err;
> + }
> +
> + /* Mapping PCI BAR regions */
> + err = pcim_iomap_regions(pdev, BIT(pdata->rg_bar), pci_name(pdev));
> + if (err) {
> + pci_err(pdev, "xData BAR I/O remapping failed\n");
> + return err;
> + }
> +
> + pci_set_master(pdev);
> +
> + /* Allocate memory */
> + dw = devm_kzalloc(&pdev->dev, sizeof(*dw), GFP_KERNEL);
> + if (!dw)
> + return -ENOMEM;
> +
> + /* Data structure initialization */
> + dw->rg_region.vaddr = pcim_iomap_table(pdev)[pdata->rg_bar];
> + if (!dw->rg_region.vaddr)
> + return -ENOMEM;
> +
> + dw->rg_region.vaddr += pdata->rg_off;
> + dw->rg_region.paddr = pdev->resource[pdata->rg_bar].start;
> + dw->rg_region.paddr += pdata->rg_off;
> + dw->rg_region.sz = pdata->rg_sz;
> +
> + dw->max_wr_len = pcie_get_mps(pdev);
> + dw->max_wr_len >>= 2;
> +
> + dw->max_rd_len = pcie_get_readrq(pdev);
> + dw->max_rd_len >>= 2;
> +
> + dw->pdev = pdev;
> +
> + writel(0x0, &(__dw_regs(dw)->RAM_addr));
> + writel(0x0, &(__dw_regs(dw)->RAM_port));
> +
> + addr = dw->rg_region.paddr + DW_XDATA_EP_MEM_OFFSET;
> + writel(lower_32_bits(addr), &(__dw_regs(dw)->addr_lsb));
> + writel(upper_32_bits(addr), &(__dw_regs(dw)->addr_msb));
> + pci_dbg(pdev, "xData: target address = 0x%.16llx\n", addr);
> +
> + pci_dbg(pdev, "xData: wr_len=%zu, rd_len=%zu\n",
> + dw->max_wr_len * 4, dw->max_rd_len * 4);
> +
> + err = sysfs_create_file(&dev->kobj, &sysfs_write_attr.attr);
> + if (err)
> + return err;
> +
> + err = sysfs_create_file(&dev->kobj, &sysfs_read_attr.attr);
> + if (err)
> + return err;
> +
> + err = sysfs_create_file(&dev->kobj, &sysfs_stop_attr.attr);
> + if (err)
> + return err;
By manually creating sysfs files, you just raced with userspace and lost
horribly.
Please never do that, use an attribute group and have the driver core
automatically create/remove your files for you.
Big hint, if you ever find yourself calling sysfs_* in a driver, you are
doing something wrong.
thanks,
greg k-h
