[PATCH 0/4] Add infrastructure needed for CRC support

[PATCH 0/4] Add infrastructure needed for CRC support

[Haneen Mohammed]

This patchset add the necessary infrastructure needed later for CRC
support.

1. add functions to map buffers to kernel address space.
2. map/unmap buffers in the prepare/cleanup_fb hooks.
3. clip plane coordinates.
4. subclass CRTC state.

Note:
This patchset was built on top of the following patchset:
subject: [PATCH V2 0/5] drm/vkms: Updates to meet basic kms_flip requirements
link: https://lists.freedesktop.org/archives/dri-devel/2018-June/180823.html

Haneen Mohammed (4):
  drm/vkms: Add functions to map GEM backing storage
  drm/vkms: map/unmap buffers in [prepare/cleanup]_fb hooks
  drm/vkms: Add atomic_helper_check_plane_state
  drm/vkms: subclass CRTC state

 drivers/gpu/drm/vkms/vkms_crtc.c  | 55 ++++++++++++++++++++++++++--
 drivers/gpu/drm/vkms/vkms_drv.c   |  2 ++
 drivers/gpu/drm/vkms/vkms_drv.h   | 13 +++++++
 drivers/gpu/drm/vkms/vkms_gem.c   | 50 ++++++++++++++++++++++++++
 drivers/gpu/drm/vkms/vkms_plane.c | 59 +++++++++++++++++++++++++++++--
 5 files changed, 174 insertions(+), 5 deletions(-)

-- 
2.17.1

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

[PATCH 1/4] drm/vkms: Add functions to map GEM backing storage

[Haneen Mohammed]

This patch add the necessary functions to map GEM
backing memory into the kernel's virtual address space.

Signed-off-by: Haneen Mohammed <hamohammed.sa@gmail.com>
---
 drivers/gpu/drm/vkms/vkms_drv.c |  2 ++
 drivers/gpu/drm/vkms/vkms_drv.h |  5 ++++
 drivers/gpu/drm/vkms/vkms_gem.c | 50 +++++++++++++++++++++++++++++++++
 3 files changed, 57 insertions(+)

diff --git a/drivers/gpu/drm/vkms/vkms_drv.c b/drivers/gpu/drm/vkms/vkms_drv.c
index fe93f8c17997..e48c8eeb495a 100644
--- a/drivers/gpu/drm/vkms/vkms_drv.c
+++ b/drivers/gpu/drm/vkms/vkms_drv.c
@@ -52,9 +52,11 @@ static struct drm_driver vkms_driver = {
 	.driver_features	= DRIVER_MODESET | DRIVER_ATOMIC | DRIVER_GEM,
 	.release		= vkms_release,
 	.fops			= &vkms_driver_fops,
+
 	.dumb_create		= vkms_dumb_create,
 	.dumb_map_offset	= vkms_dumb_map,
 	.gem_vm_ops		= &vkms_gem_vm_ops,
+	.gem_free_object_unlocked = vkms_gem_free_object,
 
 	.name			= DRIVER_NAME,
 	.desc			= DRIVER_DESC,
diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h
index 76f1720f81a5..d339a8108d85 100644
--- a/drivers/gpu/drm/vkms/vkms_drv.h
+++ b/drivers/gpu/drm/vkms/vkms_drv.h
@@ -35,6 +35,7 @@ struct vkms_gem_object {
 	struct drm_gem_object gem;
 	struct mutex pages_lock; /* Page lock used in page fault handler */
 	struct page **pages;
+	void *vaddr;
 };
 
 int vkms_crtc_init(struct drm_device *dev, struct drm_crtc *crtc,
@@ -58,4 +59,8 @@ int vkms_dumb_create(struct drm_file *file, struct drm_device *dev,
 int vkms_dumb_map(struct drm_file *file, struct drm_device *dev,
 		  u32 handle, u64 *offset);
 
+void vkms_gem_free_object(struct drm_gem_object *obj);
+
+void *vkms_gem_vmap(struct drm_gem_object *obj);
+
 #endif /* _VKMS_DRV_H_ */
diff --git a/drivers/gpu/drm/vkms/vkms_gem.c b/drivers/gpu/drm/vkms/vkms_gem.c
index 9f820f56b9e0..249855dded63 100644
--- a/drivers/gpu/drm/vkms/vkms_gem.c
+++ b/drivers/gpu/drm/vkms/vkms_gem.c
@@ -166,3 +166,53 @@ int vkms_dumb_map(struct drm_file *file, struct drm_device *dev,
 
 	return ret;
 }
+
+void vkms_gem_free_object(struct drm_gem_object *obj)
+{
+	struct vkms_gem_object *vkms_obj = container_of(obj,
+							struct vkms_gem_object,
+							gem);
+	kvfree(vkms_obj->pages);
+	mutex_destroy(&vkms_obj->pages_lock);
+	drm_gem_object_release(obj);
+	kfree(vkms_obj);
+}
+
+struct page **get_pages(struct vkms_gem_object *vkms_obj)
+{
+	struct drm_gem_object *gem_obj = &vkms_obj->gem;
+	struct page **pages = vkms_obj->pages;
+
+	if (!pages) {
+		mutex_lock(&vkms_obj->pages_lock);
+		pages = drm_gem_get_pages(gem_obj);
+		if (IS_ERR(pages)) {
+			mutex_unlock(&vkms_obj->pages_lock);
+			return pages;
+		}
+
+		vkms_obj->pages = pages;
+		mutex_unlock(&vkms_obj->pages_lock);
+	}
+
+	return pages;
+}
+
+void *vkms_gem_vmap(struct drm_gem_object *obj)
+{
+	void *vaddr = NULL;
+	struct vkms_gem_object *vkms_obj = container_of(obj,
+							struct vkms_gem_object,
+							gem);
+	unsigned int n_pages = obj->size >> PAGE_SHIFT;
+	struct page **pages = get_pages(vkms_obj);
+
+	if (IS_ERR(pages)) {
+		DRM_INFO("pages allocation failed %ld\n", PTR_ERR(pages));
+		return vaddr;
+	}
+
+	vaddr = vmap(pages, n_pages, VM_MAP, PAGE_KERNEL);
+
+	return vaddr;
+}
-- 
2.17.1

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

[PATCH 2/4] drm/vkms: map/unmap buffers in [prepare/cleanup]_fb hooks

[Haneen Mohammed]

This patch map/unmap GEM backing memory to kernel address space
in prepare/cleanup_fb respectively and cache the virtual address
for later use.

Signed-off-by: Haneen Mohammed <hamohammed.sa@gmail.com>
---
 drivers/gpu/drm/vkms/vkms_plane.c | 41 +++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/drivers/gpu/drm/vkms/vkms_plane.c b/drivers/gpu/drm/vkms/vkms_plane.c
index f7f63143f6d0..f464eb0e05dd 100644
--- a/drivers/gpu/drm/vkms/vkms_plane.c
+++ b/drivers/gpu/drm/vkms/vkms_plane.c
@@ -9,6 +9,7 @@
 #include "vkms_drv.h"
 #include <drm/drm_plane_helper.h>
 #include <drm/drm_atomic_helper.h>
+#include <drm/drm_gem_framebuffer_helper.h>
 
 static const struct drm_plane_funcs vkms_plane_funcs = {
 	.update_plane		= drm_atomic_helper_update_plane,
@@ -30,9 +31,49 @@ static void vkms_primary_plane_update(struct drm_plane *plane,
 {
 }
 
+static int vkms_prepare_fb(struct drm_plane *plane,
+			   struct drm_plane_state *state)
+{
+	struct drm_gem_object *gem_obj;
+	struct vkms_gem_object *vkms_obj;
+
+	if (!state->fb)
+		return 0;
+
+	gem_obj = drm_gem_fb_get_obj(state->fb, 0);
+	vkms_obj = container_of(gem_obj, struct vkms_gem_object, gem);
+	vkms_obj->vaddr = vkms_gem_vmap(gem_obj);
+
+	if (!vkms_obj->vaddr)
+		DRM_INFO("vmap failed\n");
+
+	return drm_gem_fb_prepare_fb(plane, state);
+}
+
+static void vkms_cleanup_fb(struct drm_plane *plane,
+			    struct drm_plane_state *old_state)
+{
+	struct drm_gem_object *gem_obj;
+	struct vkms_gem_object *vkms_obj;
+
+	if (!old_state->fb)
+		return;
+
+	gem_obj = drm_gem_fb_get_obj(old_state->fb, 0);
+	vkms_obj = container_of(gem_obj, struct vkms_gem_object, gem);
+
+	if (vkms_obj && vkms_obj->pages) {
+		vunmap(vkms_obj->vaddr);
+		drm_gem_put_pages(gem_obj, vkms_obj->pages, false, true);
+		vkms_obj->pages = NULL;
+	}
+}
+
 static const struct drm_plane_helper_funcs vkms_primary_helper_funcs = {
 	.atomic_check		= vkms_plane_atomic_check,
 	.atomic_update		= vkms_primary_plane_update,
+	.prepare_fb		= vkms_prepare_fb,
+	.cleanup_fb		= vkms_cleanup_fb,
 };
 
 struct drm_plane *vkms_plane_init(struct vkms_device *vkmsdev)
-- 
2.17.1

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

[PATCH 3/4] drm/vkms: Add atomic_helper_check_plane_state

[Haneen Mohammed]

Call atomic_helper_check_plane_state to clip plane coordinates.

Signed-off-by: Haneen Mohammed <hamohammed.sa@gmail.com>
---
 drivers/gpu/drm/vkms/vkms_plane.c | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/vkms/vkms_plane.c b/drivers/gpu/drm/vkms/vkms_plane.c
index f464eb0e05dd..bf37aebac0fb 100644
--- a/drivers/gpu/drm/vkms/vkms_plane.c
+++ b/drivers/gpu/drm/vkms/vkms_plane.c
@@ -7,9 +7,10 @@
  */
 
 #include "vkms_drv.h"
-#include <drm/drm_plane_helper.h>
+#include <drm/drm_atomic.h>
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_gem_framebuffer_helper.h>
+#include <drm/drm_plane_helper.h>
 
 static const struct drm_plane_funcs vkms_plane_funcs = {
 	.update_plane		= drm_atomic_helper_update_plane,
@@ -23,7 +24,20 @@ static const struct drm_plane_funcs vkms_plane_funcs = {
 static int vkms_plane_atomic_check(struct drm_plane *plane,
 				   struct drm_plane_state *state)
 {
-	return 0;
+	struct drm_crtc_state *crtc_state;
+
+	if (!state->fb || !state->crtc)
+		return 0;
+
+	crtc_state = drm_atomic_get_crtc_state(state->state, state->crtc);
+
+	if (IS_ERR(crtc_state))
+		return PTR_ERR(crtc_state);
+
+	return drm_atomic_helper_check_plane_state(state, crtc_state,
+						   DRM_PLANE_HELPER_NO_SCALING,
+						   DRM_PLANE_HELPER_NO_SCALING,
+						   false, true);
 }
 
 static void vkms_primary_plane_update(struct drm_plane *plane,
-- 
2.17.1

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

[PATCH 4/4] drm/vkms: subclass CRTC state

[Haneen Mohammed]

Subclass CRTC state struct to enable storing driver's private
state. This patch only adds the base drm_crtc_state struct and
the atomic functions that handle it.

Signed-off-by: Haneen Mohammed <hamohammed.sa@gmail.com>
---
 drivers/gpu/drm/vkms/vkms_crtc.c | 55 ++++++++++++++++++++++++++++++--
 drivers/gpu/drm/vkms/vkms_drv.h  |  8 +++++
 2 files changed, 60 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/vkms/vkms_crtc.c b/drivers/gpu/drm/vkms/vkms_crtc.c
index 84cc05506b09..56206437647d 100644
--- a/drivers/gpu/drm/vkms/vkms_crtc.c
+++ b/drivers/gpu/drm/vkms/vkms_crtc.c
@@ -10,13 +10,62 @@
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_crtc_helper.h>
 
+static void vkms_crtc_reset(struct drm_crtc *crtc)
+{
+	struct vkms_crtc_state *state = NULL;
+
+	if (crtc->state) {
+		state = container_of(crtc->state, struct vkms_crtc_state,
+				     base);
+		__drm_atomic_helper_crtc_destroy_state(crtc->state);
+		kfree(state);
+		crtc->state = NULL;
+	}
+
+	state = kzalloc(sizeof(*state), GFP_KERNEL);
+	if (!state)
+		return;
+
+	crtc->state = &state->base;
+	crtc->state->crtc = crtc;
+}
+
+static struct drm_crtc_state *
+vkms_crtc_duplicate_state(struct drm_crtc *crtc)
+{
+	struct vkms_crtc_state *state;
+
+	if (WARN_ON(!crtc->state))
+		return NULL;
+
+	state = kzalloc(sizeof(*state), GFP_KERNEL);
+	if (!state)
+		return NULL;
+
+	__drm_atomic_helper_crtc_duplicate_state(crtc, &state->base);
+
+	return &state->base;
+}
+
+static void vkms_crtc_destroy_state(struct drm_crtc *crtc,
+				    struct drm_crtc_state *state)
+{
+	struct vkms_crtc_state *vkms_state;
+
+	vkms_state = container_of(state, struct vkms_crtc_state, base);
+
+	__drm_atomic_helper_crtc_destroy_state(state);
+	kfree(vkms_state);
+}
+
 static const struct drm_crtc_funcs vkms_crtc_funcs = {
 	.set_config             = drm_atomic_helper_set_config,
 	.destroy                = drm_crtc_cleanup,
 	.page_flip              = drm_atomic_helper_page_flip,
-	.reset                  = drm_atomic_helper_crtc_reset,
-	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
-	.atomic_destroy_state   = drm_atomic_helper_crtc_destroy_state,
+
+	.reset                  = vkms_crtc_reset,
+	.atomic_duplicate_state = vkms_crtc_duplicate_state,
+	.atomic_destroy_state   = vkms_crtc_destroy_state,
 };
 
 static int vkms_crtc_atomic_check(struct drm_crtc *crtc,
diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h
index d339a8108d85..61e367d32308 100644
--- a/drivers/gpu/drm/vkms/vkms_drv.h
+++ b/drivers/gpu/drm/vkms/vkms_drv.h
@@ -19,6 +19,14 @@ static const u32 vkms_formats[] = {
 	DRM_FORMAT_XRGB8888,
 };
 
+/**
+ * vkms_crtc_state - Driver specific CRTC state
+ * @base: base CRTC state
+ */
+struct vkms_crtc_state {
+	struct drm_crtc_state base;
+};
+
 struct vkms_output {
 	struct drm_crtc crtc;
 	struct drm_encoder encoder;
-- 
2.17.1

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: [PATCH 1/4] drm/vkms: Add functions to map GEM backing storage

[Daniel Vetter]

On Mon, Jul 09, 2018 at 06:44:26PM +0300, Haneen Mohammed wrote:
> This patch add the necessary functions to map GEM
> backing memory into the kernel's virtual address space.
> 
> Signed-off-by: Haneen Mohammed <hamohammed.sa@gmail.com>
> ---
>  drivers/gpu/drm/vkms/vkms_drv.c |  2 ++
>  drivers/gpu/drm/vkms/vkms_drv.h |  5 ++++
>  drivers/gpu/drm/vkms/vkms_gem.c | 50 +++++++++++++++++++++++++++++++++
>  3 files changed, 57 insertions(+)
> 
> diff --git a/drivers/gpu/drm/vkms/vkms_drv.c b/drivers/gpu/drm/vkms/vkms_drv.c
> index fe93f8c17997..e48c8eeb495a 100644
> --- a/drivers/gpu/drm/vkms/vkms_drv.c
> +++ b/drivers/gpu/drm/vkms/vkms_drv.c
> @@ -52,9 +52,11 @@ static struct drm_driver vkms_driver = {
>  	.driver_features	= DRIVER_MODESET | DRIVER_ATOMIC | DRIVER_GEM,
>  	.release		= vkms_release,
>  	.fops			= &vkms_driver_fops,
> +
>  	.dumb_create		= vkms_dumb_create,
>  	.dumb_map_offset	= vkms_dumb_map,
>  	.gem_vm_ops		= &vkms_gem_vm_ops,
> +	.gem_free_object_unlocked = vkms_gem_free_object,

This is a separate bugfix, fixing a fairly huge memory leak. I think it'd
be good to catch this in the future, by adding a 

	else
		WARN(1, "no gem free callback, leaking memory\n");

to the end of drm_gem_object_free. Can you pls do that?

Also since this line here is a bugfix separate from the vmap support, can
you pls split it out?
>  
>  	.name			= DRIVER_NAME,
>  	.desc			= DRIVER_DESC,
> diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h
> index 76f1720f81a5..d339a8108d85 100644
> --- a/drivers/gpu/drm/vkms/vkms_drv.h
> +++ b/drivers/gpu/drm/vkms/vkms_drv.h
> @@ -35,6 +35,7 @@ struct vkms_gem_object {
>  	struct drm_gem_object gem;
>  	struct mutex pages_lock; /* Page lock used in page fault handler */
>  	struct page **pages;
> +	void *vaddr;
>  };
>  
>  int vkms_crtc_init(struct drm_device *dev, struct drm_crtc *crtc,
> @@ -58,4 +59,8 @@ int vkms_dumb_create(struct drm_file *file, struct drm_device *dev,
>  int vkms_dumb_map(struct drm_file *file, struct drm_device *dev,
>  		  u32 handle, u64 *offset);
>  
> +void vkms_gem_free_object(struct drm_gem_object *obj);
> +
> +void *vkms_gem_vmap(struct drm_gem_object *obj);
> +
>  #endif /* _VKMS_DRV_H_ */
> diff --git a/drivers/gpu/drm/vkms/vkms_gem.c b/drivers/gpu/drm/vkms/vkms_gem.c
> index 9f820f56b9e0..249855dded63 100644
> --- a/drivers/gpu/drm/vkms/vkms_gem.c
> +++ b/drivers/gpu/drm/vkms/vkms_gem.c
> @@ -166,3 +166,53 @@ int vkms_dumb_map(struct drm_file *file, struct drm_device *dev,
>  
>  	return ret;
>  }
> +
> +void vkms_gem_free_object(struct drm_gem_object *obj)
> +{
> +	struct vkms_gem_object *vkms_obj = container_of(obj,
> +							struct vkms_gem_object,
> +							gem);
> +	kvfree(vkms_obj->pages);

We need to put the pages here too if ->pages exists, there's a put_pages
helper for that.

Also probably a good idea to vunmap here too.

But I think both cases (i.e. vmap not yet released and pages still around)
would indicate a bug in the vkms driver of releasing the object while it's
still in use somewhere. So maybe also add a

	WARN_ON(obj->pages);
	WARN_ON(obj->vmap);

here to make sure this doesn't happen?
-Daniel

> +	mutex_destroy(&vkms_obj->pages_lock);
> +	drm_gem_object_release(obj);
> +	kfree(vkms_obj);
> +}
> +
> +struct page **get_pages(struct vkms_gem_object *vkms_obj)
> +{
> +	struct drm_gem_object *gem_obj = &vkms_obj->gem;
> +	struct page **pages = vkms_obj->pages;
> +
> +	if (!pages) {
> +		mutex_lock(&vkms_obj->pages_lock);
> +		pages = drm_gem_get_pages(gem_obj);
> +		if (IS_ERR(pages)) {
> +			mutex_unlock(&vkms_obj->pages_lock);
> +			return pages;
> +		}
> +
> +		vkms_obj->pages = pages;
> +		mutex_unlock(&vkms_obj->pages_lock);
> +	}
> +
> +	return pages;
> +}
> +
> +void *vkms_gem_vmap(struct drm_gem_object *obj)
> +{
> +	void *vaddr = NULL;
> +	struct vkms_gem_object *vkms_obj = container_of(obj,
> +							struct vkms_gem_object,
> +							gem);
> +	unsigned int n_pages = obj->size >> PAGE_SHIFT;
> +	struct page **pages = get_pages(vkms_obj);
> +
> +	if (IS_ERR(pages)) {
> +		DRM_INFO("pages allocation failed %ld\n", PTR_ERR(pages));
> +		return vaddr;
> +	}
> +
> +	vaddr = vmap(pages, n_pages, VM_MAP, PAGE_KERNEL);
> +
> +	return vaddr;
> +}
> -- 
> 2.17.1
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: [PATCH 2/4] drm/vkms: map/unmap buffers in [prepare/cleanup]_fb hooks

[Daniel Vetter]

On Mon, Jul 09, 2018 at 06:46:49PM +0300, Haneen Mohammed wrote:
> This patch map/unmap GEM backing memory to kernel address space
> in prepare/cleanup_fb respectively and cache the virtual address
> for later use.
> 
> Signed-off-by: Haneen Mohammed <hamohammed.sa@gmail.com>
> ---
>  drivers/gpu/drm/vkms/vkms_plane.c | 41 +++++++++++++++++++++++++++++++
>  1 file changed, 41 insertions(+)
> 
> diff --git a/drivers/gpu/drm/vkms/vkms_plane.c b/drivers/gpu/drm/vkms/vkms_plane.c
> index f7f63143f6d0..f464eb0e05dd 100644
> --- a/drivers/gpu/drm/vkms/vkms_plane.c
> +++ b/drivers/gpu/drm/vkms/vkms_plane.c
> @@ -9,6 +9,7 @@
>  #include "vkms_drv.h"
>  #include <drm/drm_plane_helper.h>
>  #include <drm/drm_atomic_helper.h>
> +#include <drm/drm_gem_framebuffer_helper.h>
>  
>  static const struct drm_plane_funcs vkms_plane_funcs = {
>  	.update_plane		= drm_atomic_helper_update_plane,
> @@ -30,9 +31,49 @@ static void vkms_primary_plane_update(struct drm_plane *plane,
>  {
>  }
>  
> +static int vkms_prepare_fb(struct drm_plane *plane,
> +			   struct drm_plane_state *state)
> +{
> +	struct drm_gem_object *gem_obj;
> +	struct vkms_gem_object *vkms_obj;
> +
> +	if (!state->fb)
> +		return 0;
> +
> +	gem_obj = drm_gem_fb_get_obj(state->fb, 0);
> +	vkms_obj = container_of(gem_obj, struct vkms_gem_object, gem);
> +	vkms_obj->vaddr = vkms_gem_vmap(gem_obj);
> +
> +	if (!vkms_obj->vaddr)
> +		DRM_INFO("vmap failed\n");
> +
> +	return drm_gem_fb_prepare_fb(plane, state);
> +}
> +
> +static void vkms_cleanup_fb(struct drm_plane *plane,
> +			    struct drm_plane_state *old_state)
> +{
> +	struct drm_gem_object *gem_obj;
> +	struct vkms_gem_object *vkms_obj;
> +
> +	if (!old_state->fb)
> +		return;
> +
> +	gem_obj = drm_gem_fb_get_obj(old_state->fb, 0);
> +	vkms_obj = container_of(gem_obj, struct vkms_gem_object, gem);
> +
> +	if (vkms_obj && vkms_obj->pages) {
> +		vunmap(vkms_obj->vaddr);

Please also clear obj->vaddr here.

> +		drm_gem_put_pages(gem_obj, vkms_obj->pages, false, true);
> +		vkms_obj->pages = NULL;

I think it'd be good to also have a vkms_gem_vunmap helper for this, for
symmetry and prettier code.

There's another issue: cleanup/prepare_fb can be called multiple times on
the same fb. This doesn't really happen for the current vkms case where we
only have 1 plane, but if you have more than one plane you can attach the
same fb to all of them. This means we need a vmap counter (probably best
put into the vkms_gem_v(un)map functions), and only create the actual vmap
when the counter goes from 0 -> 1, and release it only when it goes down
to 0 finally. Usually it's called vmap_use_count or so.

Ofc that needs to be protected by the buffer lock, so you need to rework
your locking a bit and pull it out into the vmap/vunmap functions.

Cheers, Daniel

> +	}
> +}
> +
>  static const struct drm_plane_helper_funcs vkms_primary_helper_funcs = {
>  	.atomic_check		= vkms_plane_atomic_check,
>  	.atomic_update		= vkms_primary_plane_update,
> +	.prepare_fb		= vkms_prepare_fb,
> +	.cleanup_fb		= vkms_cleanup_fb,
>  };
>  
>  struct drm_plane *vkms_plane_init(struct vkms_device *vkmsdev)
> -- 
> 2.17.1
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: [PATCH 3/4] drm/vkms: Add atomic_helper_check_plane_state

[Daniel Vetter]

On Mon, Jul 09, 2018 at 06:47:34PM +0300, Haneen Mohammed wrote:
> Call atomic_helper_check_plane_state to clip plane coordinates.
> 
> Signed-off-by: Haneen Mohammed <hamohammed.sa@gmail.com>
> ---
>  drivers/gpu/drm/vkms/vkms_plane.c | 18 ++++++++++++++++--
>  1 file changed, 16 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/vkms/vkms_plane.c b/drivers/gpu/drm/vkms/vkms_plane.c
> index f464eb0e05dd..bf37aebac0fb 100644
> --- a/drivers/gpu/drm/vkms/vkms_plane.c
> +++ b/drivers/gpu/drm/vkms/vkms_plane.c
> @@ -7,9 +7,10 @@
>   */
>  
>  #include "vkms_drv.h"
> -#include <drm/drm_plane_helper.h>
> +#include <drm/drm_atomic.h>
>  #include <drm/drm_atomic_helper.h>
>  #include <drm/drm_gem_framebuffer_helper.h>
> +#include <drm/drm_plane_helper.h>
>  
>  static const struct drm_plane_funcs vkms_plane_funcs = {
>  	.update_plane		= drm_atomic_helper_update_plane,
> @@ -23,7 +24,20 @@ static const struct drm_plane_funcs vkms_plane_funcs = {
>  static int vkms_plane_atomic_check(struct drm_plane *plane,
>  				   struct drm_plane_state *state)
>  {
> -	return 0;
> +	struct drm_crtc_state *crtc_state;
> +
> +	if (!state->fb || !state->crtc)
> +		return 0;
> +
> +	crtc_state = drm_atomic_get_crtc_state(state->state, state->crtc);
> +
> +	if (IS_ERR(crtc_state))
> +		return PTR_ERR(crtc_state);
> +
> +	return drm_atomic_helper_check_plane_state(state, crtc_state,
> +						   DRM_PLANE_HELPER_NO_SCALING,
> +						   DRM_PLANE_HELPER_NO_SCALING,
> +						   false, true);

So one additional thing we need to check here is plane_state->visible
(which is computed by the check_plane_state) function. For now we can't
handle a disabled primary plane (we'd need to change our crc function to
compute the crc of an all-black screen), hence need to reject this:
	ret = drm_atomic_helper_check_plane_state(state, crtc_state,
						   DRM_PLANE_HELPER_NO_SCALING,
						   DRM_PLANE_HELPER_NO_SCALING,
						   false, true);
	if (ret != 0)
		return ret;

	/* for now primary plane must be visible and full screen */
	if (!plane_state->visible)
		return -EINVAL;

	return 0;

otherwise lgtm.
-Daniel

>  }
>  
>  static void vkms_primary_plane_update(struct drm_plane *plane,
> -- 
> 2.17.1
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: [PATCH 4/4] drm/vkms: subclass CRTC state

[Daniel Vetter]

On Mon, Jul 09, 2018 at 06:48:36PM +0300, Haneen Mohammed wrote:
> Subclass CRTC state struct to enable storing driver's private
> state. This patch only adds the base drm_crtc_state struct and
> the atomic functions that handle it.
> 
> Signed-off-by: Haneen Mohammed <hamohammed.sa@gmail.com>

Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

> ---
>  drivers/gpu/drm/vkms/vkms_crtc.c | 55 ++++++++++++++++++++++++++++++--
>  drivers/gpu/drm/vkms/vkms_drv.h  |  8 +++++
>  2 files changed, 60 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/vkms/vkms_crtc.c b/drivers/gpu/drm/vkms/vkms_crtc.c
> index 84cc05506b09..56206437647d 100644
> --- a/drivers/gpu/drm/vkms/vkms_crtc.c
> +++ b/drivers/gpu/drm/vkms/vkms_crtc.c
> @@ -10,13 +10,62 @@
>  #include <drm/drm_atomic_helper.h>
>  #include <drm/drm_crtc_helper.h>
>  
> +static void vkms_crtc_reset(struct drm_crtc *crtc)
> +{
> +	struct vkms_crtc_state *state = NULL;
> +
> +	if (crtc->state) {
> +		state = container_of(crtc->state, struct vkms_crtc_state,
> +				     base);
> +		__drm_atomic_helper_crtc_destroy_state(crtc->state);
> +		kfree(state);
> +		crtc->state = NULL;
> +	}
> +
> +	state = kzalloc(sizeof(*state), GFP_KERNEL);

Hm, using kzalloc here is a good idea instead of kmalloc like in the
default functions. Care to write a patch for drm_atomic_helper to replace
all the kmalloc with kzalloc?

Thanks, Daniel

> +	if (!state)
> +		return;
> +
> +	crtc->state = &state->base;
> +	crtc->state->crtc = crtc;
> +}
> +
> +static struct drm_crtc_state *
> +vkms_crtc_duplicate_state(struct drm_crtc *crtc)
> +{
> +	struct vkms_crtc_state *state;
> +
> +	if (WARN_ON(!crtc->state))
> +		return NULL;
> +
> +	state = kzalloc(sizeof(*state), GFP_KERNEL);
> +	if (!state)
> +		return NULL;
> +
> +	__drm_atomic_helper_crtc_duplicate_state(crtc, &state->base);
> +
> +	return &state->base;
> +}
> +
> +static void vkms_crtc_destroy_state(struct drm_crtc *crtc,
> +				    struct drm_crtc_state *state)
> +{
> +	struct vkms_crtc_state *vkms_state;
> +
> +	vkms_state = container_of(state, struct vkms_crtc_state, base);
> +
> +	__drm_atomic_helper_crtc_destroy_state(state);
> +	kfree(vkms_state);
> +}
> +
>  static const struct drm_crtc_funcs vkms_crtc_funcs = {
>  	.set_config             = drm_atomic_helper_set_config,
>  	.destroy                = drm_crtc_cleanup,
>  	.page_flip              = drm_atomic_helper_page_flip,
> -	.reset                  = drm_atomic_helper_crtc_reset,
> -	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
> -	.atomic_destroy_state   = drm_atomic_helper_crtc_destroy_state,
> +
> +	.reset                  = vkms_crtc_reset,
> +	.atomic_duplicate_state = vkms_crtc_duplicate_state,
> +	.atomic_destroy_state   = vkms_crtc_destroy_state,
>  };
>  
>  static int vkms_crtc_atomic_check(struct drm_crtc *crtc,
> diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h
> index d339a8108d85..61e367d32308 100644
> --- a/drivers/gpu/drm/vkms/vkms_drv.h
> +++ b/drivers/gpu/drm/vkms/vkms_drv.h
> @@ -19,6 +19,14 @@ static const u32 vkms_formats[] = {
>  	DRM_FORMAT_XRGB8888,
>  };
>  
> +/**
> + * vkms_crtc_state - Driver specific CRTC state
> + * @base: base CRTC state
> + */
> +struct vkms_crtc_state {
> +	struct drm_crtc_state base;
> +};
> +
>  struct vkms_output {
>  	struct drm_crtc crtc;
>  	struct drm_encoder encoder;
> -- 
> 2.17.1
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: [PATCH 1/4] drm/vkms: Add functions to map GEM backing storage

[Chris Wilson]

Quoting Haneen Mohammed (2018-07-09 16:44:26)
> +struct page **get_pages(struct vkms_gem_object *vkms_obj)
> +{
> +       struct drm_gem_object *gem_obj = &vkms_obj->gem;
> +       struct page **pages = vkms_obj->pages;
> +
> +       if (!pages) {
> +               mutex_lock(&vkms_obj->pages_lock);
> +               pages = drm_gem_get_pages(gem_obj);
> +               if (IS_ERR(pages)) {
> +                       mutex_unlock(&vkms_obj->pages_lock);
> +                       return pages;
> +               }
> +
> +               vkms_obj->pages = pages;
> +               mutex_unlock(&vkms_obj->pages_lock);

You have a race here with two callers setting pages. Trivially you fix
it by checking if (!pages) again inside the lock, but the lock is
superfluous in this case:
	if (!vkms_obj->pages) {
		srtuct pages **pages;

		pages = drm_gem_get_pages(gem_obj);
		if (IS_ERR(pages))
			return pages;
		
		if (cmpxchg(&vkms_obj->pages, NULL, pages))
			put_pages(pages);

		/* barrier() is implied */
	}

	return vkms_obj->pages;
-Chris
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: [PATCH 1/4] drm/vkms: Add functions to map GEM backing storage

[Haneen Mohammed]

On Tue, Jul 10, 2018 at 09:12:36AM +0100, Chris Wilson wrote:
> Quoting Haneen Mohammed (2018-07-09 16:44:26)
> > +struct page **get_pages(struct vkms_gem_object *vkms_obj)
> > +{
> > +       struct drm_gem_object *gem_obj = &vkms_obj->gem;
> > +       struct page **pages = vkms_obj->pages;
> > +
> > +       if (!pages) {
> > +               mutex_lock(&vkms_obj->pages_lock);
> > +               pages = drm_gem_get_pages(gem_obj);
> > +               if (IS_ERR(pages)) {
> > +                       mutex_unlock(&vkms_obj->pages_lock);
> > +                       return pages;
> > +               }
> > +
> > +               vkms_obj->pages = pages;
> > +               mutex_unlock(&vkms_obj->pages_lock);
> 
> You have a race here with two callers setting pages. Trivially you fix
> it by checking if (!pages) again inside the lock, but the lock is
> superfluous in this case:
> 	if (!vkms_obj->pages) {
> 		srtuct pages **pages;
> 
> 		pages = drm_gem_get_pages(gem_obj);
> 		if (IS_ERR(pages))
> 			return pages;
> 		
> 		if (cmpxchg(&vkms_obj->pages, NULL, pages))
> 			put_pages(pages);
> 
> 		/* barrier() is implied */
> 	}
> 
> 	return vkms_obj->pages;
> -Chris

Thank you for the feedback!

- Haneen
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: [PATCH 4/4] drm/vkms: subclass CRTC state

[Haneen Mohammed]

On Tue, Jul 10, 2018 at 10:10:46AM +0200, Daniel Vetter wrote:
> On Mon, Jul 09, 2018 at 06:48:36PM +0300, Haneen Mohammed wrote:
> > Subclass CRTC state struct to enable storing driver's private
> > state. This patch only adds the base drm_crtc_state struct and
> > the atomic functions that handle it.
> > 
> > Signed-off-by: Haneen Mohammed <hamohammed.sa@gmail.com>
> 
> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> 
> > ---
> >  drivers/gpu/drm/vkms/vkms_crtc.c | 55 ++++++++++++++++++++++++++++++--
> >  drivers/gpu/drm/vkms/vkms_drv.h  |  8 +++++
> >  2 files changed, 60 insertions(+), 3 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/vkms/vkms_crtc.c b/drivers/gpu/drm/vkms/vkms_crtc.c
> > index 84cc05506b09..56206437647d 100644
> > --- a/drivers/gpu/drm/vkms/vkms_crtc.c
> > +++ b/drivers/gpu/drm/vkms/vkms_crtc.c
> > @@ -10,13 +10,62 @@
> >  #include <drm/drm_atomic_helper.h>
> >  #include <drm/drm_crtc_helper.h>
> >  
> > +static void vkms_crtc_reset(struct drm_crtc *crtc)
> > +{
> > +	struct vkms_crtc_state *state = NULL;
> > +
> > +	if (crtc->state) {
> > +		state = container_of(crtc->state, struct vkms_crtc_state,
> > +				     base);
> > +		__drm_atomic_helper_crtc_destroy_state(crtc->state);
> > +		kfree(state);
> > +		crtc->state = NULL;
> > +	}
> > +
> > +	state = kzalloc(sizeof(*state), GFP_KERNEL);
> 
> Hm, using kzalloc here is a good idea instead of kmalloc like in the
> default functions. Care to write a patch for drm_atomic_helper to replace
> all the kmalloc with kzalloc?
> 

Sure, I will work on that and on your other comments. 

Thank you so much!
Haneen

> Thanks, Daniel
> 
> > +	if (!state)
> > +		return;
> > +
> > +	crtc->state = &state->base;
> > +	crtc->state->crtc = crtc;
> > +}
> > +
> > +static struct drm_crtc_state *
> > +vkms_crtc_duplicate_state(struct drm_crtc *crtc)
> > +{
> > +	struct vkms_crtc_state *state;
> > +
> > +	if (WARN_ON(!crtc->state))
> > +		return NULL;
> > +
> > +	state = kzalloc(sizeof(*state), GFP_KERNEL);
> > +	if (!state)
> > +		return NULL;
> > +
> > +	__drm_atomic_helper_crtc_duplicate_state(crtc, &state->base);
> > +
> > +	return &state->base;
> > +}
> > +
> > +static void vkms_crtc_destroy_state(struct drm_crtc *crtc,
> > +				    struct drm_crtc_state *state)
> > +{
> > +	struct vkms_crtc_state *vkms_state;
> > +
> > +	vkms_state = container_of(state, struct vkms_crtc_state, base);
> > +
> > +	__drm_atomic_helper_crtc_destroy_state(state);
> > +	kfree(vkms_state);
> > +}
> > +
> >  static const struct drm_crtc_funcs vkms_crtc_funcs = {
> >  	.set_config             = drm_atomic_helper_set_config,
> >  	.destroy                = drm_crtc_cleanup,
> >  	.page_flip              = drm_atomic_helper_page_flip,
> > -	.reset                  = drm_atomic_helper_crtc_reset,
> > -	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
> > -	.atomic_destroy_state   = drm_atomic_helper_crtc_destroy_state,
> > +
> > +	.reset                  = vkms_crtc_reset,
> > +	.atomic_duplicate_state = vkms_crtc_duplicate_state,
> > +	.atomic_destroy_state   = vkms_crtc_destroy_state,
> >  };
> >  
> >  static int vkms_crtc_atomic_check(struct drm_crtc *crtc,
> > diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h
> > index d339a8108d85..61e367d32308 100644
> > --- a/drivers/gpu/drm/vkms/vkms_drv.h
> > +++ b/drivers/gpu/drm/vkms/vkms_drv.h
> > @@ -19,6 +19,14 @@ static const u32 vkms_formats[] = {
> >  	DRM_FORMAT_XRGB8888,
> >  };
> >  
> > +/**
> > + * vkms_crtc_state - Driver specific CRTC state
> > + * @base: base CRTC state
> > + */
> > +struct vkms_crtc_state {
> > +	struct drm_crtc_state base;
> > +};
> > +
> >  struct vkms_output {
> >  	struct drm_crtc crtc;
> >  	struct drm_encoder encoder;
> > -- 
> > 2.17.1
> > 
> 
> -- 
> Daniel Vetter
> Software Engineer, Intel Corporation
> http://blog.ffwll.ch
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel