Re: [PATCH] grvga: Fix error handling issues

Julia Lawall
2012-06-22T16:12:15Z

Maybe you could used the devm_ functions for request_mem_region and
ioremap so that the error handling can just be dropped?

julia

On Fri, 22 Jun 2012, Emil Goode wrote:

> This patch fixes two problems with the error handling in the
> grvga_probe function.
>
> - If the call to grvga_parse_custom on line 370 fails we use
> the wrong label so that release_mem_region will be called
> without a call to request_mem_region being made.
>
> - If the call to ioremap on line 436 fails we should not try
> to call iounmap. I added an if statement to check whether or
> not a call to iounmap should be made.
>
> - I also changed the names of the labels to make the code
> easier to read.
>
> Signed-off-by: Emil Goode <emilgoode@gmail.com>
> ---
> drivers/video/grvga.c | 34 ++++++++++++++++++----------------
> 1 file changed, 18 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/video/grvga.c b/drivers/video/grvga.c
> index da066c2..d9d688a 100644
> --- a/drivers/video/grvga.c
> +++ b/drivers/video/grvga.c
> @@ -354,7 +354,7 @@ static int __devinit grvga_probe(struct platform_device *dev)
> */
> if (fb_get_options("grvga", &options)) {
> retval = -ENODEV;
> - goto err;
> + goto free_fb;
> }
>
> if (!options || !*options)
> @@ -370,7 +370,7 @@ static int __devinit grvga_probe(struct platform_device *dev)
> if (grvga_parse_custom(this_opt, &info->var) < 0) {
> dev_err(&dev->dev, "Failed to parse custom mode (%s).\n", this_opt);
> retval = -EINVAL;
> - goto err1;
> + goto free_fb;
> }
> } else if (!strncmp(this_opt, "addr", 4))
> grvga_fix_addr = simple_strtoul(this_opt + 5, NULL, 16);
> @@ -390,7 +390,7 @@ static int __devinit grvga_probe(struct platform_device *dev)
> if (!request_mem_region(dev->resource[0].start, resource_size(&dev->resource[0]), "grlib-svgactrl regs")) {
> dev_err(&dev->dev, "registers already mapped\n");
> retval = -EBUSY;
> - goto err;
> + goto free_fb;
> }
>
> par->regs = of_ioremap(&dev->resource[0], 0,
> @@ -400,14 +400,14 @@ static int __devinit grvga_probe(struct platform_device *dev)
> if (!par->regs) {
> dev_err(&dev->dev, "failed to map registers\n");
> retval = -ENOMEM;
> - goto err1;
> + goto release_regs;
> }
>
> retval = fb_alloc_cmap(&info->cmap, 256, 0);
> if (retval < 0) {
> dev_err(&dev->dev, "failed to allocate mem with fb_alloc_cmap\n");
> retval = -ENOMEM;
> - goto err2;
> + goto unmap_regs;
> }
>
> if (mode_opt) {
> @@ -415,7 +415,7 @@ static int __devinit grvga_probe(struct platform_device *dev)
> grvga_modedb, sizeof(grvga_modedb), &grvga_modedb[0], 8);
> if (!retval || retval == 4) {
> retval = -EINVAL;
> - goto err3;
> + goto dealloc_cmap;
> }
> }
>
> @@ -430,7 +430,7 @@ static int __devinit grvga_probe(struct platform_device *dev)
> if (!request_mem_region(physical_start, grvga_mem_size, dev->name)) {
> dev_err(&dev->dev, "failed to request memory region\n");
> retval = -ENOMEM;
> - goto err3;
> + goto dealloc_cmap;
> }
>
> virtual_start = (unsigned long) ioremap(physical_start, grvga_mem_size);
> @@ -438,7 +438,7 @@ static int __devinit grvga_probe(struct platform_device *dev)
> if (!virtual_start) {
> dev_err(&dev->dev, "error mapping framebuffer memory\n");
> retval = -ENOMEM;
> - goto err4;
> + goto free_mem;
> }
> } else { /* Allocate frambuffer memory */
>
> @@ -451,7 +451,7 @@ static int __devinit grvga_probe(struct platform_device *dev)
> "unable to allocate framebuffer memory (%lu bytes)\n",
> grvga_mem_size);
> retval = -ENOMEM;
> - goto err3;
> + goto dealloc_cmap;
> }
>
> physical_start = dma_map_single(&dev->dev, (void *)virtual_start, grvga_mem_size, DMA_TO_DEVICE);
> @@ -484,7 +484,7 @@ static int __devinit grvga_probe(struct platform_device *dev)
> retval = register_framebuffer(info);
> if (retval < 0) {
> dev_err(&dev->dev, "failed to register framebuffer\n");
> - goto err4;
> + goto free_mem;
> }
>
> __raw_writel(physical_start, &par->regs->fb_pos);
> @@ -493,21 +493,23 @@ static int __devinit grvga_probe(struct platform_device *dev)
>
> return 0;
>
> -err4:
> +free_mem:
> dev_set_drvdata(&dev->dev, NULL);
> if (grvga_fix_addr) {
> release_mem_region(physical_start, grvga_mem_size);
> - iounmap((void *)virtual_start);
> + if (virtual_start)
> + iounmap((void *)virtual_start);
> } else
> kfree((void *)virtual_start);
> -err3:
> +
> +dealloc_cmap:
> fb_dealloc_cmap(&info->cmap);
> -err2:
> +unmap_regs:
> of_iounmap(&dev->resource[0], par->regs,
> resource_size(&dev->resource[0]));
> -err1:
> +release_regs:
> release_mem_region(dev->resource[0].start, resource_size(&dev->resource[0]));
> -err:
> +free_fb:
> framebuffer_release(info);
>
> return retval;
> --
> 1.7.10
>
> --
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