Re: [PATCH v2] media: pt3: Switch to using functions pcim_* and devm_*

[Andy Shevchenko]

On Sat, Aug 14, 2021 at 6:57 PM Evgeny Novikov <novikov@xxxxxxxxx> wrote:
>
> pt3_probe() did not free one of IO mappings in case when one of them was
> successful while another one failed. The patch fixed that by using
> functions pcim_*. Also, it simplifies error handling through switching
> to devm_* functions.
>
> Found by Linux Driver Verification project (linuxtesting.org).

Looks good to me, though I can't test this myself either (I have no hardware).
Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>

> Signed-off-by: Evgeny Novikov <novikov@xxxxxxxxx>
> Co-developed-by: Kirill Shilimanov <kirill.shilimanov@xxxxxxxxxx>
> Signed-off-by: Kirill Shilimanov <kirill.shilimanov@xxxxxxxxxx>
> ---
> v2: Use functions pcim_* and devm_* to simplify code (Andy Shevchenko)
> ---
>  drivers/media/pci/pt3/pt3.c | 58 +++++++++----------------------------
>  1 file changed, 14 insertions(+), 44 deletions(-)
>
> diff --git a/drivers/media/pci/pt3/pt3.c b/drivers/media/pci/pt3/pt3.c
> index c0bc86793355..0d51bdf01f43 100644
> --- a/drivers/media/pci/pt3/pt3.c
> +++ b/drivers/media/pci/pt3/pt3.c
> @@ -685,12 +685,6 @@ static void pt3_remove(struct pci_dev *pdev)
>         for (i = PT3_NUM_FE - 1; i >= 0; i--)
>                 pt3_cleanup_adapter(pt3, i);
>         i2c_del_adapter(&pt3->i2c_adap);
> -       kfree(pt3->i2c_buf);
> -       pci_iounmap(pt3->pdev, pt3->regs[0]);
> -       pci_iounmap(pt3->pdev, pt3->regs[1]);
> -       pci_release_regions(pdev);
> -       pci_disable_device(pdev);
> -       kfree(pt3);
>  }
>
>  static int pt3_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
> @@ -704,14 +698,14 @@ static int pt3_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
>         if (pci_read_config_byte(pdev, PCI_REVISION_ID, &rev) || rev != 1)
>                 return -ENODEV;
>
> -       ret = pci_enable_device(pdev);
> +       ret = pcim_enable_device(pdev);
>         if (ret < 0)
>                 return -ENODEV;
>         pci_set_master(pdev);
>
> -       ret = pci_request_regions(pdev, DRV_NAME);
> +       ret = pcim_iomap_regions(pdev, BIT(0) | BIT(2), DRV_NAME);
>         if (ret < 0)
> -               goto err_disable_device;
> +               return ret;
>
>         ret = dma_set_mask(&pdev->dev, DMA_BIT_MASK(64));
>         if (ret == 0)
> @@ -722,42 +716,32 @@ static int pt3_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
>                         dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32));
>                 else {
>                         dev_err(&pdev->dev, "Failed to set DMA mask\n");
> -                       goto err_release_regions;
> +                       return ret;
>                 }
>                 dev_info(&pdev->dev, "Use 32bit DMA\n");
>         }
>
> -       pt3 = kzalloc(sizeof(*pt3), GFP_KERNEL);
> -       if (!pt3) {
> -               ret = -ENOMEM;
> -               goto err_release_regions;
> -       }
> +       pt3 = devm_kzalloc(&pdev->dev, sizeof(*pt3), GFP_KERNEL);
> +       if (!pt3)
> +               return -ENOMEM;
>         pci_set_drvdata(pdev, pt3);
>         pt3->pdev = pdev;
>         mutex_init(&pt3->lock);
> -       pt3->regs[0] = pci_ioremap_bar(pdev, 0);
> -       pt3->regs[1] = pci_ioremap_bar(pdev, 2);
> -       if (pt3->regs[0] == NULL || pt3->regs[1] == NULL) {
> -               dev_err(&pdev->dev, "Failed to ioremap\n");
> -               ret = -ENOMEM;
> -               goto err_kfree;
> -       }
> +       pt3->regs[0] = pcim_iomap_table(pdev)[0];
> +       pt3->regs[1] = pcim_iomap_table(pdev)[2];
>
>         ver = ioread32(pt3->regs[0] + REG_VERSION);
>         if ((ver >> 16) != 0x0301) {
>                 dev_warn(&pdev->dev, "PT%d, I/F-ver.:%d not supported\n",
>                          ver >> 24, (ver & 0x00ff0000) >> 16);
> -               ret = -ENODEV;
> -               goto err_iounmap;
> +               return -ENODEV;
>         }
>
>         pt3->num_bufs = clamp_val(num_bufs, MIN_DATA_BUFS, MAX_DATA_BUFS);
>
> -       pt3->i2c_buf = kmalloc(sizeof(*pt3->i2c_buf), GFP_KERNEL);
> -       if (pt3->i2c_buf == NULL) {
> -               ret = -ENOMEM;
> -               goto err_iounmap;
> -       }
> +       pt3->i2c_buf = devm_kmalloc(&pdev->dev, sizeof(*pt3->i2c_buf), GFP_KERNEL);
> +       if (!pt3->i2c_buf)
> +               return -ENOMEM;
>         i2c = &pt3->i2c_adap;
>         i2c->owner = THIS_MODULE;
>         i2c->algo = &pt3_i2c_algo;
> @@ -767,7 +751,7 @@ static int pt3_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
>         i2c_set_adapdata(i2c, pt3);
>         ret = i2c_add_adapter(i2c);
>         if (ret < 0)
> -               goto err_i2cbuf;
> +               return ret;
>
>         for (i = 0; i < PT3_NUM_FE; i++) {
>                 ret = pt3_alloc_adapter(pt3, i);
> @@ -799,21 +783,7 @@ static int pt3_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
>         while (i >= 0)
>                 pt3_cleanup_adapter(pt3, i--);
>         i2c_del_adapter(i2c);
> -err_i2cbuf:
> -       kfree(pt3->i2c_buf);
> -err_iounmap:
> -       if (pt3->regs[0])
> -               pci_iounmap(pdev, pt3->regs[0]);
> -       if (pt3->regs[1])
> -               pci_iounmap(pdev, pt3->regs[1]);
> -err_kfree:
> -       kfree(pt3);
> -err_release_regions:
> -       pci_release_regions(pdev);
> -err_disable_device:
> -       pci_disable_device(pdev);
>         return ret;
> -
>  }
>
>  static const struct pci_device_id pt3_id_table[] = {
> --
> 2.26.2
>


-- 
With Best Regards,
Andy Shevchenko