2012-08-17 16:50:35

by Emil Goode

Subject: [PATCH] staging: drm/omap: Add error handling

From: Emil Goode <[email protected]>

This patch adds fail checks for kmalloc and kzalloc calls
and also adds a error path that frees allocated pages by
introducing a call to _drm_gem_put_pages.

Signed-off-by: Emil Goode <[email protected]>
---
drivers/staging/omapdrm/omap_gem.c | 17 ++++++++++++++++-
1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/omapdrm/omap_gem.c b/drivers/staging/omapdrm/omap_gem.c
index 74082aa..c828743 100644
--- a/drivers/staging/omapdrm/omap_gem.c
+++ b/drivers/staging/omapdrm/omap_gem.c
@@ -226,7 +226,8 @@ static int omap_gem_attach_pages(struct drm_gem_object *obj)
struct drm_device *dev = obj->dev;
struct omap_gem_object *omap_obj = to_omap_bo(obj);
struct page **pages;
- int i, npages = obj->size >> PAGE_SHIFT;
+ int npages = obj->size >> PAGE_SHIFT;
+ int i, ret;
dma_addr_t *addrs;

WARN_ON(omap_obj->pages);
@@ -246,18 +247,32 @@ static int omap_gem_attach_pages(struct drm_gem_object *obj)
*/
if (omap_obj->flags & (OMAP_BO_WC|OMAP_BO_UNCACHED)) {
addrs = kmalloc(npages * sizeof(addrs), GFP_KERNEL);
+ if (!addrs) {
+ ret = -ENOMEM;
+ goto free_pages;
+ }
+
for (i = 0; i < npages; i++) {
addrs[i] = dma_map_page(dev->dev, pages[i],
0, PAGE_SIZE, DMA_BIDIRECTIONAL);
}
} else {
addrs = kzalloc(npages * sizeof(addrs), GFP_KERNEL);
+ if (!addrs) {
+ ret = -ENOMEM;
+ goto free_pages;
+ }
}

omap_obj->addrs = addrs;
omap_obj->pages = pages;

return 0;
+
+free_pages:
+ _drm_gem_put_pages(obj, pages, true, false);
+
+ return ret;
}

/** release backing pages */
--
1.7.10.4

2012-08-17 17:27:14

by Clark, Rob

Subject: Re: [PATCH] staging: drm/omap: Add error handling

On Fri, Aug 17, 2012 at 11:53 AM, <[email protected]> wrote:
> From: Emil Goode <[email protected]>
>
> This patch adds fail checks for kmalloc and kzalloc calls
> and also adds a error path that frees allocated pages by
> introducing a call to _drm_gem_put_pages.
>
> Signed-off-by: Emil Goode <[email protected]>

Looks good, thanks

Signed-off-by: Rob Clark <[email protected]>

> ---
> drivers/staging/omapdrm/omap_gem.c | 17 ++++++++++++++++-
> 1 file changed, 16 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/staging/omapdrm/omap_gem.c b/drivers/staging/omapdrm/omap_gem.c
> index 74082aa..c828743 100644
> --- a/drivers/staging/omapdrm/omap_gem.c
> +++ b/drivers/staging/omapdrm/omap_gem.c
> @@ -226,7 +226,8 @@ static int omap_gem_attach_pages(struct drm_gem_object *obj)
> struct drm_device *dev = obj->dev;
> struct omap_gem_object *omap_obj = to_omap_bo(obj);
> struct page **pages;
> - int i, npages = obj->size >> PAGE_SHIFT;
> + int npages = obj->size >> PAGE_SHIFT;
> + int i, ret;
> dma_addr_t *addrs;
>
> WARN_ON(omap_obj->pages);
> @@ -246,18 +247,32 @@ static int omap_gem_attach_pages(struct drm_gem_object *obj)
> */
> if (omap_obj->flags & (OMAP_BO_WC|OMAP_BO_UNCACHED)) {
> addrs = kmalloc(npages * sizeof(addrs), GFP_KERNEL);
> + if (!addrs) {
> + ret = -ENOMEM;
> + goto free_pages;
> + }
> +
> for (i = 0; i < npages; i++) {
> addrs[i] = dma_map_page(dev->dev, pages[i],
> 0, PAGE_SIZE, DMA_BIDIRECTIONAL);
> }
> } else {
> addrs = kzalloc(npages * sizeof(addrs), GFP_KERNEL);
> + if (!addrs) {
> + ret = -ENOMEM;
> + goto free_pages;
> + }
> }
>
> omap_obj->addrs = addrs;
> omap_obj->pages = pages;
>
> return 0;
> +
> +free_pages:
> + _drm_gem_put_pages(obj, pages, true, false);
> +
> + return ret;
> }
>
> /** release backing pages */
> --
> 1.7.10.4
>