diff options
| author | Sasha Finkelstein <fnkl.kernel@gmail.com> | 2025-01-09 22:45:46 +0100 |
|---|---|---|
| committer | Dmitry Osipenko <dmitry.osipenko@collabora.com> | 2025-01-25 00:16:57 +0300 |
| commit | 7f3b11934f9684038555fd9160e188d6893949b9 (patch) | |
| tree | 6744970d41b94fcd433f76a975bab21bd521f33f /drivers/gpu/drm/virtio/virtgpu_vram.c | |
| parent | 3ab334814dc7dff39075e055e12847d51878916e (diff) | |
drm/virtio: Support partial maps of GEM objects
Those are useful to implement coherent cross-vm mmap.
Signed-off-by: Sasha Finkelstein <fnkl.kernel@gmail.com>
Reviewed-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Tested-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250109-virtgpu-gem-partial-map-v1-1-a914b48776bd@gmail.com
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
[dmitry.osipenko@collabora.com: Corrected vm_size check to account vm_pgoff]
Diffstat (limited to 'drivers/gpu/drm/virtio/virtgpu_vram.c')
| -rw-r--r-- | drivers/gpu/drm/virtio/virtgpu_vram.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/drivers/gpu/drm/virtio/virtgpu_vram.c b/drivers/gpu/drm/virtio/virtgpu_vram.c index 25df81c02783..5ad3b7c6f73c 100644 --- a/drivers/gpu/drm/virtio/virtgpu_vram.c +++ b/drivers/gpu/drm/virtio/virtgpu_vram.c @@ -37,6 +37,7 @@ static int virtio_gpu_vram_mmap(struct drm_gem_object *obj, struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(obj); struct virtio_gpu_object_vram *vram = to_virtio_gpu_vram(bo); unsigned long vm_size = vma->vm_end - vma->vm_start; + unsigned long vm_end; if (!(bo->blob_flags & VIRTGPU_BLOB_FLAG_USE_MAPPABLE)) return -EINVAL; @@ -56,12 +57,14 @@ static int virtio_gpu_vram_mmap(struct drm_gem_object *obj, else if (vram->map_info == VIRTIO_GPU_MAP_CACHE_UNCACHED) vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); - /* Partial mappings of GEM buffers don't happen much in practice. */ - if (vm_size != vram->vram_node.size) + if (check_add_overflow(vma->vm_pgoff << PAGE_SHIFT, vm_size, &vm_end)) + return -EINVAL; + + if (vm_end > vram->vram_node.size) return -EINVAL; ret = io_remap_pfn_range(vma, vma->vm_start, - vram->vram_node.start >> PAGE_SHIFT, + (vram->vram_node.start >> PAGE_SHIFT) + vma->vm_pgoff, vm_size, vma->vm_page_prot); return ret; } |