| Message ID | 20200408191224.947302-1-arnd@arndb.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm: work around dma_addr_t/resource_size_t mixup warning | expand |
The fix got stuck a bit, I just pushed it out, should make it to the
next linux-next:
commit b2ecb89c27a4fd110187e0afeca70557215f55a1 (drm-misc-next-fixes)
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date: Thu Apr 2 22:59:26 2020 +0100
drm/legacy: Fix type for drm_local_map.offset
Cheers, Daniel
On Wed, Apr 8, 2020 at 9:12 PM Arnd Bergmann <arnd@arndb.de> wrote:
>
> On configurations with 64-bit dma_addr_t but 32-bit resource_size_t,
> there is now a warning:
>
> drivers/gpu/drm/drm_bufs.c: In function 'drm_addmap_core':
> drivers/gpu/drm/drm_bufs.c:328:8: error: passing argument 3 of 'dma_alloc_coherent' from incompatible pointer type [-Werror=incompatible-pointer-types]
> 328 | &map->offset,
> | ^~~~~~~~~~~~
> | |
> | resource_size_t * {aka unsigned int *}
> In file included from include/linux/pci-dma-compat.h:8,
> from include/linux/pci.h:2392,
> from include/drm/drm_pci.h:35,
> from drivers/gpu/drm/drm_bufs.c:46:
> include/linux/dma-mapping.h:642:15: note: expected 'dma_addr_t *' {aka 'long long unsigned int *'} but argument is of type 'resource_size_t *' {aka 'unsigned int *'}
> 642 | dma_addr_t *dma_handle, gfp_t gfp)
> | ~~~~~~~~~~~~^~~~~~~~~~
>
> I have no idea if this is safe on targets that may need a high DMA address,
> or why we store a DMA address token in a resource_size_t in the first place,
> but using a temporary variable avoids the warning.
>
> Fixes: 8e4ff9b56957 ("drm: Remove the dma_alloc_coherent wrapper for internal usage")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
> drivers/gpu/drm/drm_bufs.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/drm_bufs.c b/drivers/gpu/drm/drm_bufs.c
> index dcabf5698333..0fbe65c62f1e 100644
> --- a/drivers/gpu/drm/drm_bufs.c
> +++ b/drivers/gpu/drm/drm_bufs.c
> @@ -149,6 +149,7 @@ static int drm_addmap_core(struct drm_device *dev, resource_size_t offset,
> {
> struct drm_local_map *map;
> struct drm_map_list *list;
> + dma_addr_t dma_addr;
> unsigned long user_token;
> int ret;
>
> @@ -325,8 +326,9 @@ static int drm_addmap_core(struct drm_device *dev, resource_size_t offset,
> * need to point to a 64bit variable first. */
> map->handle = dma_alloc_coherent(&dev->pdev->dev,
> map->size,
> - &map->offset,
> + &dma_addr,
> GFP_KERNEL);
> + map->offset = (resource_size_t)dma_addr;
> if (!map->handle) {
> kfree(map);
> return -ENOMEM;
> --
> 2.26.0
>
diff --git a/drivers/gpu/drm/drm_bufs.c b/drivers/gpu/drm/drm_bufs.c index dcabf5698333..0fbe65c62f1e 100644 --- a/drivers/gpu/drm/drm_bufs.c +++ b/drivers/gpu/drm/drm_bufs.c @@ -149,6 +149,7 @@ static int drm_addmap_core(struct drm_device *dev, resource_size_t offset, { struct drm_local_map *map; struct drm_map_list *list; + dma_addr_t dma_addr; unsigned long user_token; int ret; @@ -325,8 +326,9 @@ static int drm_addmap_core(struct drm_device *dev, resource_size_t offset, * need to point to a 64bit variable first. */ map->handle = dma_alloc_coherent(&dev->pdev->dev, map->size, - &map->offset, + &dma_addr, GFP_KERNEL); + map->offset = (resource_size_t)dma_addr; if (!map->handle) { kfree(map); return -ENOMEM;
On configurations with 64-bit dma_addr_t but 32-bit resource_size_t, there is now a warning: drivers/gpu/drm/drm_bufs.c: In function 'drm_addmap_core': drivers/gpu/drm/drm_bufs.c:328:8: error: passing argument 3 of 'dma_alloc_coherent' from incompatible pointer type [-Werror=incompatible-pointer-types] 328 | &map->offset, | ^~~~~~~~~~~~ | | | resource_size_t * {aka unsigned int *} In file included from include/linux/pci-dma-compat.h:8, from include/linux/pci.h:2392, from include/drm/drm_pci.h:35, from drivers/gpu/drm/drm_bufs.c:46: include/linux/dma-mapping.h:642:15: note: expected 'dma_addr_t *' {aka 'long long unsigned int *'} but argument is of type 'resource_size_t *' {aka 'unsigned int *'} 642 | dma_addr_t *dma_handle, gfp_t gfp) | ~~~~~~~~~~~~^~~~~~~~~~ I have no idea if this is safe on targets that may need a high DMA address, or why we store a DMA address token in a resource_size_t in the first place, but using a temporary variable avoids the warning. Fixes: 8e4ff9b56957 ("drm: Remove the dma_alloc_coherent wrapper for internal usage") Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- drivers/gpu/drm/drm_bufs.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)