On device removal reroute all CPU mappings to dummy page per drm_file instance or imported GEM object.
Signed-off-by: Andrey Grodzovsky andrey.grodzovsky@amd.com --- drivers/gpu/drm/ttm/ttm_bo_vm.c | 65 ++++++++++++++++++++++++++++++++++++----- 1 file changed, 57 insertions(+), 8 deletions(-)
diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c index 389128b..2f8bf5e 100644 --- a/drivers/gpu/drm/ttm/ttm_bo_vm.c +++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c @@ -35,6 +35,8 @@ #include <drm/ttm/ttm_bo_driver.h> #include <drm/ttm/ttm_placement.h> #include <drm/drm_vma_manager.h> +#include <drm/drm_drv.h> +#include <drm/drm_file.h> #include <linux/mm.h> #include <linux/pfn_t.h> #include <linux/rbtree.h> @@ -328,19 +330,66 @@ vm_fault_t ttm_bo_vm_fault(struct vm_fault *vmf) pgprot_t prot; struct ttm_buffer_object *bo = vma->vm_private_data; vm_fault_t ret; + int idx; + struct drm_device *ddev = bo->base.dev;
- ret = ttm_bo_vm_reserve(bo, vmf); - if (ret) - return ret; + if (drm_dev_enter(ddev, &idx)) { + ret = ttm_bo_vm_reserve(bo, vmf); + if (ret) + goto exit; + + prot = vma->vm_page_prot;
- prot = vma->vm_page_prot; - ret = ttm_bo_vm_fault_reserved(vmf, prot, TTM_BO_VM_NUM_PREFAULT); - if (ret == VM_FAULT_RETRY && !(vmf->flags & FAULT_FLAG_RETRY_NOWAIT)) + ret = ttm_bo_vm_fault_reserved(vmf, prot, TTM_BO_VM_NUM_PREFAULT); + if (ret == VM_FAULT_RETRY && !(vmf->flags & FAULT_FLAG_RETRY_NOWAIT)) + goto exit; + + dma_resv_unlock(bo->base.resv); + +exit: + drm_dev_exit(idx); return ret; + } else {
- dma_resv_unlock(bo->base.resv); + struct drm_file *file = NULL; + struct page *dummy_page = NULL; + int handle;
- return ret; + /* We are faulting on imported BO from dma_buf */ + if (bo->base.dma_buf && bo->base.import_attach) { + dummy_page = bo->base.dummy_page; + /* We are faulting on non imported BO, find drm_file owning the BO*/ + } else { + struct drm_gem_object *gobj; + + mutex_lock(&ddev->filelist_mutex); + list_for_each_entry(file, &ddev->filelist, lhead) { + spin_lock(&file->table_lock); + idr_for_each_entry(&file->object_idr, gobj, handle) { + if (gobj == &bo->base) { + dummy_page = file->dummy_page; + break; + } + } + spin_unlock(&file->table_lock); + } + mutex_unlock(&ddev->filelist_mutex); + } + + if (dummy_page) { + /* + * Let do_fault complete the PTE install e.t.c using vmf->page + * + * TODO - should i call free_page somewhere ? + */ + get_page(dummy_page); + vmf->page = dummy_page; + return 0; + } else { + return VM_FAULT_SIGSEGV; + } + } } EXPORT_SYMBOL(ttm_bo_vm_fault);