| Message ID | 20190516141447.46839-3-steven.price@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/panfrost: drm_gem_map_offset() helper | expand |
On 16/05/2019 21:26, Daniel Vetter wrote: > On Thu, May 16, 2019 at 03:14:46PM +0100, Steven Price wrote: >> Provide a wrapper for drm_gem_map_offset() for clients of shmem. This >> wrapper provides the correct semantics for the drm_gem_shmem_mmap() >> callback. >> >> Signed-off-by: Steven Price <steven.price@arm.com> >> --- >> drivers/gpu/drm/drm_gem_shmem_helper.c | 20 ++++++++++++++++++++ >> include/drm/drm_gem_shmem_helper.h | 2 ++ >> 2 files changed, 22 insertions(+) >> >> diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c >> index 1ee208c2c85e..9dbebc4897d1 100644 >> --- a/drivers/gpu/drm/drm_gem_shmem_helper.c >> +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c >> @@ -400,6 +400,26 @@ int drm_gem_shmem_dumb_create(struct drm_file *file, struct drm_device *dev, >> } >> EXPORT_SYMBOL_GPL(drm_gem_shmem_dumb_create); >> >> +/** >> + * drm_gem_map_offset - return the fake mmap offset for a gem object >> + * @file: drm file-private structure containing the gem object >> + * @dev: corresponding drm_device >> + * @handle: gem object handle >> + * @offset: return location for the fake mmap offset >> + * >> + * This provides an offset suitable for user space to return to the >> + * drm_gem_shmem_mmap() callback via an mmap() call. >> + * >> + * Returns: >> + * 0 on success or a negative error code on failure. >> + */ >> +int drm_gem_shmem_map_offset(struct drm_file *file, struct drm_device *dev, >> + u32 handle, u64 *offset) >> +{ >> + return drm_gem_map_offset(file, dev, handle, offset); >> +} >> +EXPORT_SYMBOL_GPL(drm_gem_shmem_map_offset); > > Not seeing the point of this mapper, since drm_gem_shmem_map_offset isn't > speficic at all. It works for dumb, shmem, cma and private objects all > equally well. I'd drop this and just directly call the underlying thing, > no need to layer helpers. > -Daniel Ok, I'll drop it. I may have misunderstood, but I think Chris Wilson was asking for it because shmem is the source of the particular requirements of what can be mmap()d. But I think a helper can be added very easily if anything changes, so this patch is probably premature. I'll resend the series with this patch dropped. Thanks, Steve
diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c index 1ee208c2c85e..9dbebc4897d1 100644 --- a/drivers/gpu/drm/drm_gem_shmem_helper.c +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c @@ -400,6 +400,26 @@ int drm_gem_shmem_dumb_create(struct drm_file *file, struct drm_device *dev, } EXPORT_SYMBOL_GPL(drm_gem_shmem_dumb_create); +/** + * drm_gem_map_offset - return the fake mmap offset for a gem object + * @file: drm file-private structure containing the gem object + * @dev: corresponding drm_device + * @handle: gem object handle + * @offset: return location for the fake mmap offset + * + * This provides an offset suitable for user space to return to the + * drm_gem_shmem_mmap() callback via an mmap() call. + * + * Returns: + * 0 on success or a negative error code on failure. + */ +int drm_gem_shmem_map_offset(struct drm_file *file, struct drm_device *dev, + u32 handle, u64 *offset) +{ + return drm_gem_map_offset(file, dev, handle, offset); +} +EXPORT_SYMBOL_GPL(drm_gem_shmem_map_offset); + static vm_fault_t drm_gem_shmem_fault(struct vm_fault *vmf) { struct vm_area_struct *vma = vmf->vma; diff --git a/include/drm/drm_gem_shmem_helper.h b/include/drm/drm_gem_shmem_helper.h index 038b6d313447..4239ddaaaa4f 100644 --- a/include/drm/drm_gem_shmem_helper.h +++ b/include/drm/drm_gem_shmem_helper.h @@ -128,6 +128,8 @@ drm_gem_shmem_create_with_handle(struct drm_file *file_priv, int drm_gem_shmem_dumb_create(struct drm_file *file, struct drm_device *dev, struct drm_mode_create_dumb *args); +int drm_gem_shmem_map_offset(struct drm_file *file, struct drm_device *dev, + u32 handle, u64 *offset); int drm_gem_shmem_mmap(struct file *filp, struct vm_area_struct *vma); extern const struct vm_operations_struct drm_gem_shmem_vm_ops;
Provide a wrapper for drm_gem_map_offset() for clients of shmem. This wrapper provides the correct semantics for the drm_gem_shmem_mmap() callback. Signed-off-by: Steven Price <steven.price@arm.com> --- drivers/gpu/drm/drm_gem_shmem_helper.c | 20 ++++++++++++++++++++ include/drm/drm_gem_shmem_helper.h | 2 ++ 2 files changed, 22 insertions(+)