From c97f082c135210da06a82c373fb660f8bfd57d95 Mon Sep 17 00:00:00 2001 From: Andrey Grodzovsky Date: Fri, 27 Aug 2021 16:39:08 -0400 Subject: drm/ttm: Clear all DMA mappings on demand MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Used by drivers supporting hot unplug to handle all DMA IOMMU group related dependencies before the group is removed during device removal and we try to access it after free when last device pointer from user space is dropped. v3: Switch to ttm_bo_get_unless_zerom Iterate bdev for pinned list Switch to ttm_tt_unpopulate Signed-off-by: Andrey Grodzovsky Reviewed-by: Christian König Link: https://patchwork.freedesktop.org/patch/msgid/20210827203910.5565-3-andrey.grodzovsky@amd.com --- drivers/gpu/drm/ttm/ttm_device.c | 47 ++++++++++++++++++++++++++++++++++++++++ include/drm/ttm/ttm_device.h | 1 + 2 files changed, 48 insertions(+) diff --git a/drivers/gpu/drm/ttm/ttm_device.c b/drivers/gpu/drm/ttm/ttm_device.c index 9eb8f54b66fc..a021d029b730 100644 --- a/drivers/gpu/drm/ttm/ttm_device.c +++ b/drivers/gpu/drm/ttm/ttm_device.c @@ -248,3 +248,50 @@ void ttm_device_fini(struct ttm_device *bdev) ttm_global_release(); } EXPORT_SYMBOL(ttm_device_fini); + +void ttm_device_clear_dma_mappings(struct ttm_device *bdev) +{ + struct ttm_resource_manager *man; + struct ttm_buffer_object *bo; + unsigned int i, j; + + spin_lock(&bdev->lru_lock); + while (!list_empty(&bdev->pinned)) { + bo = list_first_entry(&bdev->pinned, struct ttm_buffer_object, lru); + /* Take ref against racing releases once lru_lock is unlocked */ + if (ttm_bo_get_unless_zero(bo)) { + list_del_init(&bo->lru); + spin_unlock(&bdev->lru_lock); + + if (bo->ttm) + ttm_tt_unpopulate(bo->bdev, bo->ttm); + + ttm_bo_put(bo); + spin_lock(&bdev->lru_lock); + } + } + + for (i = TTM_PL_SYSTEM; i < TTM_NUM_MEM_TYPES; ++i) { + man = ttm_manager_type(bdev, i); + if (!man || !man->use_tt) + continue; + + for (j = 0; j < TTM_MAX_BO_PRIORITY; ++j) { + while (!list_empty(&man->lru[j])) { + bo = list_first_entry(&man->lru[j], struct ttm_buffer_object, lru); + if (ttm_bo_get_unless_zero(bo)) { + list_del_init(&bo->lru); + spin_unlock(&bdev->lru_lock); + + if (bo->ttm) + ttm_tt_unpopulate(bo->bdev, bo->ttm); + + ttm_bo_put(bo); + spin_lock(&bdev->lru_lock); + } + } + } + } + spin_unlock(&bdev->lru_lock); +} +EXPORT_SYMBOL(ttm_device_clear_dma_mappings); diff --git a/include/drm/ttm/ttm_device.h b/include/drm/ttm/ttm_device.h index 03fb44d061e0..07d722950d5b 100644 --- a/include/drm/ttm/ttm_device.h +++ b/include/drm/ttm/ttm_device.h @@ -299,5 +299,6 @@ int ttm_device_init(struct ttm_device *bdev, struct ttm_device_funcs *funcs, struct drm_vma_offset_manager *vma_manager, bool use_dma_alloc, bool use_dma32); void ttm_device_fini(struct ttm_device *bdev); +void ttm_device_clear_dma_mappings(struct ttm_device *bdev); #endif -- cgit v1.2.3