From 30b5144ca41266ffc6071c33eea4076b66ac5eb9 Mon Sep 17 00:00:00 2001 From: Dmitry Osipenko Date: Tue, 30 May 2023 01:39:31 +0300 Subject: [PATCH] dma-buf/heaps: Don't assert held reservation lock for dma-buf mmapping Don't assert held dma-buf reservation lock on memory mapping of exported buffer. We're going to change dma-buf mmap() locking policy such that exporters will have to handle the lock. The previous locking policy caused deadlock problem for DRM drivers in a case of self-imported dma-bufs once these drivers are moved to use reservation lock universally. The problem solved by moving the lock down to exporters. This patch prepares dma-buf heaps for the locking policy update. Reviewed-by: Emil Velikov Signed-off-by: Dmitry Osipenko Link: https://patchwork.freedesktop.org/patch/msgid/20230529223935.2672495-3-dmitry.osipenko@collabora.com --- drivers/dma-buf/heaps/cma_heap.c | 3 --- drivers/dma-buf/heaps/system_heap.c | 3 --- 2 files changed, 6 deletions(-) diff --git a/drivers/dma-buf/heaps/cma_heap.c b/drivers/dma-buf/heaps/cma_heap.c index a7f048048864..ee899f8e6721 100644 --- a/drivers/dma-buf/heaps/cma_heap.c +++ b/drivers/dma-buf/heaps/cma_heap.c @@ -13,7 +13,6 @@ #include #include #include -#include #include #include #include @@ -183,8 +182,6 @@ static int cma_heap_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma) { struct cma_heap_buffer *buffer = dmabuf->priv; - dma_resv_assert_held(dmabuf->resv); - if ((vma->vm_flags & (VM_SHARED | VM_MAYSHARE)) == 0) return -EINVAL; diff --git a/drivers/dma-buf/heaps/system_heap.c b/drivers/dma-buf/heaps/system_heap.c index ee7059399e9c..9076d47ed2ef 100644 --- a/drivers/dma-buf/heaps/system_heap.c +++ b/drivers/dma-buf/heaps/system_heap.c @@ -13,7 +13,6 @@ #include #include #include -#include #include #include #include @@ -201,8 +200,6 @@ static int system_heap_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma) struct sg_page_iter piter; int ret; - dma_resv_assert_held(dmabuf->resv); - for_each_sgtable_page(table, &piter, vma->vm_pgoff) { struct page *page = sg_page_iter_page(&piter); -- 2.34.1