On Fri, Aug 29, 2014 at 12:12:41PM +0200, David Herrmann wrote:
> Lets use kasprintf() to avoid pre-allocating the buffer. This is really
> nothing to optimize for speed and the input is trusted, so kasprintf() is
> just fine.
>
> Signed-off-by: David Herrmann <dh.herrmann at gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter at ffwll.ch>
> ---
> drivers/gpu/drm/drm_pci.c | 30 ++++++++----------------------
> drivers/gpu/drm/drm_platform.c | 31 ++++++++-----------------------
> 2 files changed, 16 insertions(+), 45 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_pci.c b/drivers/gpu/drm/drm_pci.c
> index 020cfd9..8efea6b 100644
> --- a/drivers/gpu/drm/drm_pci.c
> +++ b/drivers/gpu/drm/drm_pci.c
> @@ -129,31 +129,17 @@ static int drm_get_pci_domain(struct drm_device *dev)
>
> static int drm_pci_set_busid(struct drm_device *dev, struct drm_master
> *master)
> {
> - int len, ret;
> - master->unique_len = 40;
> - master->unique_size = master->unique_len;
> - master->unique = kmalloc(master->unique_size, GFP_KERNEL);
> - if (master->unique == NULL)
> + master->unique = kasprintf(GFP_KERNEL, "pci:%04x:%02x:%02x.%d",
> + drm_get_pci_domain(dev),
> + dev->pdev->bus->number,
> + PCI_SLOT(dev->pdev->devfn),
> + PCI_FUNC(dev->pdev->devfn));
> + if (!master->unique)
> return -ENOMEM;
>
> -
> - len = snprintf(master->unique, master->unique_len,
> - "pci:%04x:%02x:%02x.%d",
> - drm_get_pci_domain(dev),
> - dev->pdev->bus->number,
> - PCI_SLOT(dev->pdev->devfn),
> - PCI_FUNC(dev->pdev->devfn));
> -
> - if (len >= master->unique_len) {
> - DRM_ERROR("buffer overflow");
> - ret = -EINVAL;
> - goto err;
> - } else
> - master->unique_len = len;
> -
> + master->unique_len = strlen(master->unique);
> + master->unique_size = master->unique_len + 1;
> return 0;
> -err:
> - return ret;
> }
>
> int drm_pci_set_unique(struct drm_device *dev,
> diff --git a/drivers/gpu/drm/drm_platform.c b/drivers/gpu/drm/drm_platform.c
> index d5b76f1..0c09ddd 100644
> --- a/drivers/gpu/drm/drm_platform.c
> +++ b/drivers/gpu/drm/drm_platform.c
> @@ -70,35 +70,20 @@ err_free:
>
> static int drm_platform_set_busid(struct drm_device *dev, struct drm_master
> *master)
> {
> - int len, ret, id;
> -
> - master->unique_len = 13 + strlen(dev->platformdev->name);
> - master->unique_size = master->unique_len;
> - master->unique = kmalloc(master->unique_len + 1, GFP_KERNEL);
> -
> - if (master->unique == NULL)
> - return -ENOMEM;
> + int id;
>
> id = dev->platformdev->id;
> -
> - /* if only a single instance of the platform device, id will be
> - * set to -1.. use 0 instead to avoid a funny looking bus-id:
> - */
> - if (id == -1)
> + if (id < 0)
> id = 0;
>
> - len = snprintf(master->unique, master->unique_len,
> - "platform:%s:%02d", dev->platformdev->name, id);
> -
> - if (len > master->unique_len) {
> - DRM_ERROR("Unique buffer overflowed\n");
> - ret = -EINVAL;
> - goto err;
> - }
> + master->unique = kasprintf(GFP_KERNEL, "platform:%s:%02d",
> + dev->platformdev->name, id);
> + if (!master->unique)
> + return -ENOMEM;
>
> + master->unique_len = strlen(master->unique);
> + master->unique_size = master->unique_len;
> return 0;
> -err:
> - return ret;
> }
>
> static struct drm_bus drm_platform_bus = {
> --
> 2.1.0
>
--
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch
