Move dma_buf_mmap() function to the dynamic locking specification by taking the reservation lock. Neither of the today's drivers take the reservation lock within the mmap() callback, hence it's safe to enforce the locking.
Acked-by: Sumit Semwal sumit.semwal@linaro.org Acked-by: Christian König christian.koenig@amd.com Signed-off-by: Dmitry Osipenko dmitry.osipenko@collabora.com --- drivers/dma-buf/dma-buf.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index bff5a70b8735..2452b4c82584 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -1390,6 +1390,8 @@ EXPORT_SYMBOL_NS_GPL(dma_buf_end_cpu_access, DMA_BUF); int dma_buf_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma, unsigned long pgoff) { + int ret; + if (WARN_ON(!dmabuf || !vma)) return -EINVAL;
@@ -1410,7 +1412,11 @@ int dma_buf_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma, vma_set_file(vma, dmabuf->file); vma->vm_pgoff = pgoff;
- return dmabuf->ops->mmap(dmabuf, vma); + dma_resv_lock(dmabuf->resv, NULL); + ret = dmabuf->ops->mmap(dmabuf, vma); + dma_resv_unlock(dmabuf->resv); + + return ret; } EXPORT_SYMBOL_NS_GPL(dma_buf_mmap, DMA_BUF);