Am 21.11.20 um 06:21 schrieb Andrey Grodzovsky:
Will be used to reroute CPU mapped BO's page faults once
device is removed.
Uff, one page for each exported DMA-buf? That's not something we can do.
We need to find a different approach here.
Can't we call alloc_page() on each fault and link them together so they
are freed when the device is finally reaped?
Regards,
Christian.
Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@xxxxxxx>
---
drivers/gpu/drm/drm_file.c | 8 ++++++++
drivers/gpu/drm/drm_prime.c | 10 ++++++++++
include/drm/drm_file.h | 2 ++
include/drm/drm_gem.h | 2 ++
4 files changed, 22 insertions(+)
diff --git a/drivers/gpu/drm/drm_file.c b/drivers/gpu/drm/drm_file.c
index 0ac4566..ff3d39f 100644
--- a/drivers/gpu/drm/drm_file.c
+++ b/drivers/gpu/drm/drm_file.c
@@ -193,6 +193,12 @@ struct drm_file *drm_file_alloc(struct drm_minor *minor)
goto out_prime_destroy;
}
+ file->dummy_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
+ if (!file->dummy_page) {
+ ret = -ENOMEM;
+ goto out_prime_destroy;
+ }
+
return file;
out_prime_destroy:
@@ -289,6 +295,8 @@ void drm_file_free(struct drm_file *file)
if (dev->driver->postclose)
dev->driver->postclose(dev, file);
+ __free_page(file->dummy_page);
+
drm_prime_destroy_file_private(&file->prime);
WARN_ON(!list_empty(&file->event_list));
diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c
index 1693aa7..987b45c 100644
--- a/drivers/gpu/drm/drm_prime.c
+++ b/drivers/gpu/drm/drm_prime.c
@@ -335,6 +335,13 @@ int drm_gem_prime_fd_to_handle(struct drm_device *dev,
ret = drm_prime_add_buf_handle(&file_priv->prime,
dma_buf, *handle);
+
+ if (!ret) {
+ obj->dummy_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
+ if (!obj->dummy_page)
+ ret = -ENOMEM;
+ }
+
mutex_unlock(&file_priv->prime.lock);
if (ret)
goto fail;
@@ -1020,6 +1027,9 @@ void drm_prime_gem_destroy(struct drm_gem_object *obj, struct sg_table *sg)
dma_buf_unmap_attachment(attach, sg, DMA_BIDIRECTIONAL);
dma_buf = attach->dmabuf;
dma_buf_detach(attach->dmabuf, attach);
+
+ __free_page(obj->dummy_page);
+
/* remove the reference */
dma_buf_put(dma_buf);
}
diff --git a/include/drm/drm_file.h b/include/drm/drm_file.h
index 716990b..2a011fc 100644
--- a/include/drm/drm_file.h
+++ b/include/drm/drm_file.h
@@ -346,6 +346,8 @@ struct drm_file {
*/
struct drm_prime_file_private prime;
+ struct page *dummy_page;
+
/* private: */
#if IS_ENABLED(CONFIG_DRM_LEGACY)
unsigned long lock_count; /* DRI1 legacy lock count */
diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h
index 337a483..76a97a3 100644
--- a/include/drm/drm_gem.h
+++ b/include/drm/drm_gem.h
@@ -311,6 +311,8 @@ struct drm_gem_object {
*
*/
const struct drm_gem_object_funcs *funcs;
+
+ struct page *dummy_page;
};
/**
_______________________________________________
dri-devel mailing list
dri-devel@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/dri-devel
