We were already keeping a refcount of # of prepares (pins), to clear the iova array. Use that to avoid unpinning the iova until the last cleanup (unpin). This way, when msm_gem_unpin_iova() actually tears down the mapping, we won't have problems if the fb is being scanned out on another display (for example).
Signed-off-by: Rob Clark <robin.cl...@oss.qualcomm.com> --- drivers/gpu/drm/msm/msm_fb.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/msm/msm_fb.c b/drivers/gpu/drm/msm/msm_fb.c index 8a3b88130f4d..3b17d83f6673 100644 --- a/drivers/gpu/drm/msm/msm_fb.c +++ b/drivers/gpu/drm/msm/msm_fb.c @@ -85,7 +85,8 @@ int msm_framebuffer_prepare(struct drm_framebuffer *fb, bool needs_dirtyfb) if (needs_dirtyfb) refcount_inc(&msm_fb->dirtyfb); - atomic_inc(&msm_fb->prepare_count); + if (atomic_inc_return(&msm_fb->prepare_count) > 1) + return 0; for (i = 0; i < n; i++) { ret = msm_gem_get_and_pin_iova(fb->obj[i], vm, &msm_fb->iova[i]); @@ -108,11 +109,13 @@ void msm_framebuffer_cleanup(struct drm_framebuffer *fb, bool needed_dirtyfb) if (needed_dirtyfb) refcount_dec(&msm_fb->dirtyfb); + if (atomic_dec_return(&msm_fb->prepare_count)) + return; + + memset(msm_fb->iova, 0, sizeof(msm_fb->iova)); + for (i = 0; i < n; i++) msm_gem_unpin_iova(fb->obj[i], vm); - - if (!atomic_dec_return(&msm_fb->prepare_count)) - memset(msm_fb->iova, 0, sizeof(msm_fb->iova)); } uint32_t msm_framebuffer_iova(struct drm_framebuffer *fb, int plane) -- 2.49.0