On 17/04/2025 10:32, Boris Brezillon wrote:
Right now the DRM_PANTHOR_BO_NO_MMAP flag is ignored by
panthor_ioctl_bo_mmap_offset(), meaning BOs with this flag set can
have a file offset but can't be mapped anyway, because
panthor_gem_mmap() will filter them out.
If we error out at mmap_offset creation time, we can get rid of
panthor_gem_mmap() and call drm_gem_shmem_object_mmap directly, and
we get rid of this inconsistency of having an mmap offset for a
BO that can never be mmap-ed.
Changes in v2:
- Get rid of panthor_gem_mmap()
- Get rid of the Fixes tag and adjust the commit message accordingly
- Return ENOPERM instead of EINVAL
Signed-off-by: Boris Brezillon <boris.brezil...@collabora.com>
---
drivers/gpu/drm/panthor/panthor_drv.c | 5 +++++
drivers/gpu/drm/panthor/panthor_gem.c | 13 +------------
2 files changed, 6 insertions(+), 12 deletions(-)
diff --git a/drivers/gpu/drm/panthor/panthor_drv.c
b/drivers/gpu/drm/panthor/panthor_drv.c
index 06fe46e32073..7cd131af340d 100644
--- a/drivers/gpu/drm/panthor/panthor_drv.c
+++ b/drivers/gpu/drm/panthor/panthor_drv.c
@@ -940,6 +940,7 @@ static int panthor_ioctl_bo_mmap_offset(struct drm_device
*ddev, void *data,
struct drm_file *file)
{
struct drm_panthor_bo_mmap_offset *args = data;
+ struct panthor_gem_object *bo;
struct drm_gem_object *obj;
int ret;
@@ -950,6 +951,10 @@ static int panthor_ioctl_bo_mmap_offset(struct drm_device *ddev, void *data,
if (!obj)
return -ENOENT;
+ bo = to_panthor_bo(obj);
+ if (bo->flags & DRM_PANTHOR_BO_NO_MMAP)
+ return -EPERM;
Just a drive-by-comment: are we not leaking the bo ref here?
+
ret = drm_gem_create_mmap_offset(obj);
if (ret)
goto out;
diff --git a/drivers/gpu/drm/panthor/panthor_gem.c
b/drivers/gpu/drm/panthor/panthor_gem.c
index fd014ccc3bfc..22d78cef9c66 100644
--- a/drivers/gpu/drm/panthor/panthor_gem.c
+++ b/drivers/gpu/drm/panthor/panthor_gem.c
@@ -129,17 +129,6 @@ panthor_kernel_bo_create(struct panthor_device *ptdev,
struct panthor_vm *vm,
return ERR_PTR(ret);
}
-static int panthor_gem_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma)
-{
- struct panthor_gem_object *bo = to_panthor_bo(obj);
-
- /* Don't allow mmap on objects that have the NO_MMAP flag set. */
- if (bo->flags & DRM_PANTHOR_BO_NO_MMAP)
- return -EINVAL;
-
- return drm_gem_shmem_object_mmap(obj, vma);
-}
-
static struct dma_buf *
panthor_gem_prime_export(struct drm_gem_object *obj, int flags)
{
@@ -169,7 +158,7 @@ static const struct drm_gem_object_funcs panthor_gem_funcs
= {
.get_sg_table = drm_gem_shmem_object_get_sg_table,
.vmap = drm_gem_shmem_object_vmap,
.vunmap = drm_gem_shmem_object_vunmap,
- .mmap = panthor_gem_mmap,
+ .mmap = drm_gem_shmem_object_mmap,
.status = panthor_gem_status,
.export = panthor_gem_prime_export,
.vm_ops = &drm_gem_shmem_vm_ops,
