[PATCH 0/3] Small i915/exynos prime cleanup

[PATCH 0/3] Small i915/exynos prime cleanup

[Daniel Vetter]

Hi all,

I need to get my prime fixes in since they're blocking QA from running -nightly
prime tests. Which is a prerequisite of mine before I start touching dma-buf for
real to look at fencing and ww-mutex integration for i915.

These three patches are just a bit of prep cleanup and one bugfix that Maarten
spotted.

Cheers, Daniel

Daniel Vetter (3):
  drm: use common drm_gem_dmabuf_release in i915/exynos drivers
  drm/i915: unpin backing storage in dmabuf_unmap
  drm/i915: explicit store base gem object in dma_buf->priv

 drivers/gpu/drm/drm_prime.c                |  3 ++-
 drivers/gpu/drm/exynos/exynos_drm_dmabuf.c | 23 +-------------------
 drivers/gpu/drm/i915/i915_gem_dmabuf.c     | 34 +++++++++++++-----------------
 include/drm/drmP.h                         |  1 +
 4 files changed, 19 insertions(+), 42 deletions(-)

-- 
1.8.3.2

[PATCH 1/3] drm: use common drm_gem_dmabuf_release in i915/exynos drivers

[Daniel Vetter]

Note that this is slightly tricky since both drivers store their
native objects in dma_buf->priv. But both also embed the base
drm_gem_object at the first position, so the implicit cast is ok.

To use the release helper we need to export it, too.

Cc: Inki Dae <inki.dae@samsung.com>
Cc: Intel Graphics Development <intel-gfx@lists.freedesktop.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
---
 drivers/gpu/drm/drm_prime.c                |  3 ++-
 drivers/gpu/drm/exynos/exynos_drm_dmabuf.c | 23 +----------------------
 drivers/gpu/drm/i915/i915_gem_dmabuf.c     | 13 +------------
 include/drm/drmP.h                         |  1 +
 4 files changed, 5 insertions(+), 35 deletions(-)

diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c
index 85e450e..a35f206 100644
--- a/drivers/gpu/drm/drm_prime.c
+++ b/drivers/gpu/drm/drm_prime.c
@@ -192,7 +192,7 @@ static void drm_gem_unmap_dma_buf(struct dma_buf_attachment *attach,
 	/* nothing to be done here */
 }
 
-static void drm_gem_dmabuf_release(struct dma_buf *dma_buf)
+void drm_gem_dmabuf_release(struct dma_buf *dma_buf)
 {
 	struct drm_gem_object *obj = dma_buf->priv;
 
@@ -202,6 +202,7 @@ static void drm_gem_dmabuf_release(struct dma_buf *dma_buf)
 		drm_gem_object_unreference_unlocked(obj);
 	}
 }
+EXPORT_SYMBOL(drm_gem_dmabuf_release);
 
 static void *drm_gem_dmabuf_vmap(struct dma_buf *dma_buf)
 {
diff --git a/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c b/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c
index a0f997e..3cd56e1 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c
@@ -127,27 +127,6 @@ static void exynos_gem_unmap_dma_buf(struct dma_buf_attachment *attach,
 	/* Nothing to do. */
 }
 
-static void exynos_dmabuf_release(struct dma_buf *dmabuf)
-{
-	struct exynos_drm_gem_obj *exynos_gem_obj = dmabuf->priv;
-
-	/*
-	 * exynos_dmabuf_release() call means that file object's
-	 * f_count is 0 and it calls drm_gem_object_handle_unreference()
-	 * to drop the references that these values had been increased
-	 * at drm_prime_handle_to_fd()
-	 */
-	if (exynos_gem_obj->base.export_dma_buf == dmabuf) {
-		exynos_gem_obj->base.export_dma_buf = NULL;
-
-		/*
-		 * drop this gem object refcount to release allocated buffer
-		 * and resources.
-		 */
-		drm_gem_object_unreference_unlocked(&exynos_gem_obj->base);
-	}
-}
-
 static void *exynos_gem_dmabuf_kmap_atomic(struct dma_buf *dma_buf,
 						unsigned long page_num)
 {
@@ -193,7 +172,7 @@ static struct dma_buf_ops exynos_dmabuf_ops = {
 	.kunmap			= exynos_gem_dmabuf_kunmap,
 	.kunmap_atomic		= exynos_gem_dmabuf_kunmap_atomic,
 	.mmap			= exynos_gem_dmabuf_mmap,
-	.release		= exynos_dmabuf_release,
+	.release		= drm_gem_dmabuf_release,
 };
 
 struct dma_buf *exynos_dmabuf_prime_export(struct drm_device *drm_dev,
diff --git a/drivers/gpu/drm/i915/i915_gem_dmabuf.c b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
index f2e185c..63ee1a9 100644
--- a/drivers/gpu/drm/i915/i915_gem_dmabuf.c
+++ b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
@@ -90,17 +90,6 @@ static void i915_gem_unmap_dma_buf(struct dma_buf_attachment *attachment,
 	kfree(sg);
 }
 
-static void i915_gem_dmabuf_release(struct dma_buf *dma_buf)
-{
-	struct drm_i915_gem_object *obj = dma_buf->priv;
-
-	if (obj->base.export_dma_buf == dma_buf) {
-		/* drop the reference on the export fd holds */
-		obj->base.export_dma_buf = NULL;
-		drm_gem_object_unreference_unlocked(&obj->base);
-	}
-}
-
 static void *i915_gem_dmabuf_vmap(struct dma_buf *dma_buf)
 {
 	struct drm_i915_gem_object *obj = dma_buf->priv;
@@ -211,7 +200,7 @@ static int i915_gem_begin_cpu_access(struct dma_buf *dma_buf, size_t start, size
 static const struct dma_buf_ops i915_dmabuf_ops =  {
 	.map_dma_buf = i915_gem_map_dma_buf,
 	.unmap_dma_buf = i915_gem_unmap_dma_buf,
-	.release = i915_gem_dmabuf_release,
+	.release = drm_gem_dmabuf_release,
 	.kmap = i915_gem_dmabuf_kmap,
 	.kmap_atomic = i915_gem_dmabuf_kmap_atomic,
 	.kunmap = i915_gem_dmabuf_kunmap,
diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index 4b518e0..cc991a2 100644
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -1537,6 +1537,7 @@ extern struct drm_gem_object *drm_gem_prime_import(struct drm_device *dev,
 		struct dma_buf *dma_buf);
 extern int drm_gem_prime_fd_to_handle(struct drm_device *dev,
 		struct drm_file *file_priv, int prime_fd, uint32_t *handle);
+extern void drm_gem_dmabuf_release(struct dma_buf *dma_buf);
 
 extern int drm_prime_handle_to_fd_ioctl(struct drm_device *dev, void *data,
 					struct drm_file *file_priv);
-- 
1.8.3.2

[PATCH 2/3] drm/i915: unpin backing storage in dmabuf_unmap

[Daniel Vetter]

This fixes a WARN in i915_gem_free_object when the
obj->pages_pin_count isn't 0.

Reported-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
---
 drivers/gpu/drm/i915/i915_gem_dmabuf.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_gem_dmabuf.c b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
index 63ee1a9..0bf3d51 100644
--- a/drivers/gpu/drm/i915/i915_gem_dmabuf.c
+++ b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
@@ -85,9 +85,13 @@ static void i915_gem_unmap_dma_buf(struct dma_buf_attachment *attachment,
 				   struct sg_table *sg,
 				   enum dma_data_direction dir)
 {
+	struct drm_i915_gem_object *obj = attachment->dmabuf->priv;
+
 	dma_unmap_sg(attachment->dev, sg->sgl, sg->nents, dir);
 	sg_free_table(sg);
 	kfree(sg);
+
+	i915_gem_object_unpin_pages(obj);
 }
 
 static void *i915_gem_dmabuf_vmap(struct dma_buf *dma_buf)
-- 
1.8.3.2

[PATCH 3/3] drm/i915: explicit store base gem object in dma_buf->priv

[Daniel Vetter]

Makes it more obviously correct what tricks we play by reusing the drm
prime release helper.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
---
 drivers/gpu/drm/i915/i915_gem_dmabuf.c | 21 ++++++++++++---------
 1 file changed, 12 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem_dmabuf.c b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
index 0bf3d51..3c0edaf 100644
--- a/drivers/gpu/drm/i915/i915_gem_dmabuf.c
+++ b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
@@ -27,10 +27,15 @@
 #include "i915_drv.h"
 #include <linux/dma-buf.h>
 
+static struct drm_i915_gem_object *dma_buf_to_obj(struct dma_buf *buf)
+{
+	return to_intel_bo(buf->priv);
+}
+
 static struct sg_table *i915_gem_map_dma_buf(struct dma_buf_attachment *attachment,
 					     enum dma_data_direction dir)
 {
-	struct drm_i915_gem_object *obj = attachment->dmabuf->priv;
+	struct drm_i915_gem_object *obj = dma_buf_to_obj(attachment->dmabuf);
 	struct sg_table *st;
 	struct scatterlist *src, *dst;
 	int ret, i;
@@ -85,7 +90,7 @@ static void i915_gem_unmap_dma_buf(struct dma_buf_attachment *attachment,
 				   struct sg_table *sg,
 				   enum dma_data_direction dir)
 {
-	struct drm_i915_gem_object *obj = attachment->dmabuf->priv;
+	struct drm_i915_gem_object *obj = dma_buf_to_obj(attachment->dmabuf);
 
 	dma_unmap_sg(attachment->dev, sg->sgl, sg->nents, dir);
 	sg_free_table(sg);
@@ -96,7 +101,7 @@ static void i915_gem_unmap_dma_buf(struct dma_buf_attachment *attachment,
 
 static void *i915_gem_dmabuf_vmap(struct dma_buf *dma_buf)
 {
-	struct drm_i915_gem_object *obj = dma_buf->priv;
+	struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
 	struct drm_device *dev = obj->base.dev;
 	struct sg_page_iter sg_iter;
 	struct page **pages;
@@ -144,7 +149,7 @@ error:
 
 static void i915_gem_dmabuf_vunmap(struct dma_buf *dma_buf, void *vaddr)
 {
-	struct drm_i915_gem_object *obj = dma_buf->priv;
+	struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
 	struct drm_device *dev = obj->base.dev;
 	int ret;
 
@@ -187,7 +192,7 @@ static int i915_gem_dmabuf_mmap(struct dma_buf *dma_buf, struct vm_area_struct *
 
 static int i915_gem_begin_cpu_access(struct dma_buf *dma_buf, size_t start, size_t length, enum dma_data_direction direction)
 {
-	struct drm_i915_gem_object *obj = dma_buf->priv;
+	struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
 	struct drm_device *dev = obj->base.dev;
 	int ret;
 	bool write = (direction == DMA_BIDIRECTIONAL || direction == DMA_TO_DEVICE);
@@ -218,9 +223,7 @@ static const struct dma_buf_ops i915_dmabuf_ops =  {
 struct dma_buf *i915_gem_prime_export(struct drm_device *dev,
 				      struct drm_gem_object *gem_obj, int flags)
 {
-	struct drm_i915_gem_object *obj = to_intel_bo(gem_obj);
-
-	return dma_buf_export(obj, &i915_dmabuf_ops, obj->base.size, flags);
+	return dma_buf_export(gem_obj, &i915_dmabuf_ops, gem_obj->size, flags);
 }
 
 static int i915_gem_object_get_pages_dmabuf(struct drm_i915_gem_object *obj)
@@ -257,7 +260,7 @@ struct drm_gem_object *i915_gem_prime_import(struct drm_device *dev,
 
 	/* is this one of own objects? */
 	if (dma_buf->ops == &i915_dmabuf_ops) {
-		obj = dma_buf->priv;
+		obj = dma_buf_to_obj(dma_buf);
 		/* is it from our device? */
 		if (obj->base.dev == dev) {
 			/*
-- 
1.8.3.2

Re: [PATCH 2/3] drm/i915: unpin backing storage in dmabuf_unmap

[Daniel Vetter]

On Wed, Aug 07, 2013 at 11:15:07AM +0200, Daniel Vetter wrote:
> This fixes a WARN in i915_gem_free_object when the
> obj->pages_pin_count isn't 0.
> 
> Reported-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
> Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>
> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=67391

> ---
>  drivers/gpu/drm/i915/i915_gem_dmabuf.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/i915_gem_dmabuf.c b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
> index 63ee1a9..0bf3d51 100644
> --- a/drivers/gpu/drm/i915/i915_gem_dmabuf.c
> +++ b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
> @@ -85,9 +85,13 @@ static void i915_gem_unmap_dma_buf(struct dma_buf_attachment *attachment,
>  				   struct sg_table *sg,
>  				   enum dma_data_direction dir)
>  {
> +	struct drm_i915_gem_object *obj = attachment->dmabuf->priv;
> +
>  	dma_unmap_sg(attachment->dev, sg->sgl, sg->nents, dir);
>  	sg_free_table(sg);
>  	kfree(sg);
> +
> +	i915_gem_object_unpin_pages(obj);
>  }
>  
>  static void *i915_gem_dmabuf_vmap(struct dma_buf *dma_buf)
> -- 
> 1.8.3.2
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch

Re: [Intel-gfx] [PATCH 2/3] drm/i915: unpin backing storage in dmabuf_unmap

[Chris Wilson]

On Wed, Aug 07, 2013 at 11:15:07AM +0200, Daniel Vetter wrote:
> This fixes a WARN in i915_gem_free_object when the
> obj->pages_pin_count isn't 0.
> 
> Reported-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
> Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>
> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Papers over the WARN with iffy locking. Not all callers hold
struct_mutex, right? Worse some do, some don't...

What's the long term plan here?
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre

Re: [Intel-gfx] [PATCH 1/3] drm: use common drm_gem_dmabuf_release in i915/exynos drivers

[Chris Wilson]

On Wed, Aug 07, 2013 at 11:15:06AM +0200, Daniel Vetter wrote:
> Note that this is slightly tricky since both drivers store their
> native objects in dma_buf->priv. But both also embed the base
> drm_gem_object at the first position, so the implicit cast is ok.
> 
> To use the release helper we need to export it, too.
> 
> Cc: Inki Dae <inki.dae@samsung.com>
> Cc: Intel Graphics Development <intel-gfx@lists.freedesktop.org>
> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Any perverse driver could always call into drm_gem_dmabuf_release() with
container_of().

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre

Re: [PATCH 1/3] drm: use common drm_gem_dmabuf_release in i915/exynos drivers

[Inki Dae]

> -----Original Message-----
> From: Daniel Vetter [mailto:daniel.vetter@ffwll.ch]
> Sent: Wednesday, August 07, 2013 6:15 PM
> To: DRI Development
> Cc: Intel Graphics Development; Daniel Vetter; Inki Dae
> Subject: [PATCH 1/3] drm: use common drm_gem_dmabuf_release in i915/exynos
> drivers
> 
> Note that this is slightly tricky since both drivers store their
> native objects in dma_buf->priv. But both also embed the base
> drm_gem_object at the first position, so the implicit cast is ok.
> 
> To use the release helper we need to export it, too.

Yeah, may I repost this patch with additional work?  We also need to export
with a gem object instead of specific one like you did.

Thanks,
Inki Dae

> 
> Cc: Inki Dae <inki.dae@samsung.com>
> Cc: Intel Graphics Development <intel-gfx@lists.freedesktop.org>
> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> ---
>  drivers/gpu/drm/drm_prime.c                |  3 ++-
>  drivers/gpu/drm/exynos/exynos_drm_dmabuf.c | 23 +----------------------
>  drivers/gpu/drm/i915/i915_gem_dmabuf.c     | 13 +------------
>  include/drm/drmP.h                         |  1 +
>  4 files changed, 5 insertions(+), 35 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c
> index 85e450e..a35f206 100644
> --- a/drivers/gpu/drm/drm_prime.c
> +++ b/drivers/gpu/drm/drm_prime.c
> @@ -192,7 +192,7 @@ static void drm_gem_unmap_dma_buf(struct
> dma_buf_attachment *attach,
>  	/* nothing to be done here */
>  }
> 
> -static void drm_gem_dmabuf_release(struct dma_buf *dma_buf)
> +void drm_gem_dmabuf_release(struct dma_buf *dma_buf)
>  {
>  	struct drm_gem_object *obj = dma_buf->priv;
> 
> @@ -202,6 +202,7 @@ static void drm_gem_dmabuf_release(struct dma_buf
> *dma_buf)
>  		drm_gem_object_unreference_unlocked(obj);
>  	}
>  }
> +EXPORT_SYMBOL(drm_gem_dmabuf_release);
> 
>  static void *drm_gem_dmabuf_vmap(struct dma_buf *dma_buf)
>  {
> diff --git a/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c
> b/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c
> index a0f997e..3cd56e1 100644
> --- a/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c
> +++ b/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c
> @@ -127,27 +127,6 @@ static void exynos_gem_unmap_dma_buf(struct
> dma_buf_attachment *attach,
>  	/* Nothing to do. */
>  }
> 
> -static void exynos_dmabuf_release(struct dma_buf *dmabuf)
> -{
> -	struct exynos_drm_gem_obj *exynos_gem_obj = dmabuf->priv;
> -
> -	/*
> -	 * exynos_dmabuf_release() call means that file object's
> -	 * f_count is 0 and it calls drm_gem_object_handle_unreference()
> -	 * to drop the references that these values had been increased
> -	 * at drm_prime_handle_to_fd()
> -	 */
> -	if (exynos_gem_obj->base.export_dma_buf == dmabuf) {
> -		exynos_gem_obj->base.export_dma_buf = NULL;
> -
> -		/*
> -		 * drop this gem object refcount to release allocated buffer
> -		 * and resources.
> -		 */
> -		drm_gem_object_unreference_unlocked(&exynos_gem_obj->base);
> -	}
> -}
> -
>  static void *exynos_gem_dmabuf_kmap_atomic(struct dma_buf *dma_buf,
>  						unsigned long page_num)
>  {
> @@ -193,7 +172,7 @@ static struct dma_buf_ops exynos_dmabuf_ops = {
>  	.kunmap			= exynos_gem_dmabuf_kunmap,
>  	.kunmap_atomic		= exynos_gem_dmabuf_kunmap_atomic,
>  	.mmap			= exynos_gem_dmabuf_mmap,
> -	.release		= exynos_dmabuf_release,
> +	.release		= drm_gem_dmabuf_release,
>  };
> 
>  struct dma_buf *exynos_dmabuf_prime_export(struct drm_device *drm_dev,
> diff --git a/drivers/gpu/drm/i915/i915_gem_dmabuf.c
> b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
> index f2e185c..63ee1a9 100644
> --- a/drivers/gpu/drm/i915/i915_gem_dmabuf.c
> +++ b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
> @@ -90,17 +90,6 @@ static void i915_gem_unmap_dma_buf(struct
> dma_buf_attachment *attachment,
>  	kfree(sg);
>  }
> 
> -static void i915_gem_dmabuf_release(struct dma_buf *dma_buf)
> -{
> -	struct drm_i915_gem_object *obj = dma_buf->priv;
> -
> -	if (obj->base.export_dma_buf == dma_buf) {
> -		/* drop the reference on the export fd holds */
> -		obj->base.export_dma_buf = NULL;
> -		drm_gem_object_unreference_unlocked(&obj->base);
> -	}
> -}
> -
>  static void *i915_gem_dmabuf_vmap(struct dma_buf *dma_buf)
>  {
>  	struct drm_i915_gem_object *obj = dma_buf->priv;
> @@ -211,7 +200,7 @@ static int i915_gem_begin_cpu_access(struct dma_buf
> *dma_buf, size_t start, size
>  static const struct dma_buf_ops i915_dmabuf_ops =  {
>  	.map_dma_buf = i915_gem_map_dma_buf,
>  	.unmap_dma_buf = i915_gem_unmap_dma_buf,
> -	.release = i915_gem_dmabuf_release,
> +	.release = drm_gem_dmabuf_release,
>  	.kmap = i915_gem_dmabuf_kmap,
>  	.kmap_atomic = i915_gem_dmabuf_kmap_atomic,
>  	.kunmap = i915_gem_dmabuf_kunmap,
> diff --git a/include/drm/drmP.h b/include/drm/drmP.h
> index 4b518e0..cc991a2 100644
> --- a/include/drm/drmP.h
> +++ b/include/drm/drmP.h
> @@ -1537,6 +1537,7 @@ extern struct drm_gem_object
> *drm_gem_prime_import(struct drm_device *dev,
>  		struct dma_buf *dma_buf);
>  extern int drm_gem_prime_fd_to_handle(struct drm_device *dev,
>  		struct drm_file *file_priv, int prime_fd, uint32_t *handle);
> +extern void drm_gem_dmabuf_release(struct dma_buf *dma_buf);
> 
>  extern int drm_prime_handle_to_fd_ioctl(struct drm_device *dev, void
> *data,
>  					struct drm_file *file_priv);
> --
> 1.8.3.2

Re: [PATCH 3/3] drm/i915: explicit store base gem object in dma_buf->priv

[Chris Wilson]

On Wed, Aug 07, 2013 at 11:15:08AM +0200, Daniel Vetter wrote:
> Makes it more obviously correct what tricks we play by reusing the drm
> prime release helper.
> 
> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

I do like these little typesafe cast helpers.
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre

Re: [Intel-gfx] [PATCH 2/3] drm/i915: unpin backing storage in dmabuf_unmap

[Daniel Vetter]

On Wed, Aug 7, 2013 at 11:29 AM, Chris Wilson <chris@chris-wilson.co.uk> wrote:
> On Wed, Aug 07, 2013 at 11:15:07AM +0200, Daniel Vetter wrote:
>> This fixes a WARN in i915_gem_free_object when the
>> obj->pages_pin_count isn't 0.
>>
>> Reported-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
>> Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>
>> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
>
> Papers over the WARN with iffy locking. Not all callers hold
> struct_mutex, right? Worse some do, some don't...

Oops, that needs mutex locking here. I've checked the code and none of
the callers here  should ever hold our own dev->struct_mutex (due to
the self-import checks we bypass dma-buf for our own objects) so no
immediate deadlock. But it's easy to create circles and piss off
lockded ofc.

> What's the long term plan here?

Per-bo locking with ww mutexes. Locking is done by the callers of
map/unmap, sonce only those can properly do the ww locking dance on
all relevent buffers of a batch upfront. It's going to be fun ;-)

Looking closer I've also spotted that our map_buf callback has a call
to i915_mutex_lock_interruptible, which means the map can fail with
-EINTR. Currently it seems unspec'ed whether map is allowed to do
that, but current callers certainly can't cope with this. I'll throw a
2nd patch on top.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch

Re: [PATCH 1/3] drm: use common drm_gem_dmabuf_release in i915/exynos drivers

[Daniel Vetter]

On Wed, Aug 7, 2013 at 11:40 AM, Inki Dae <inki.dae@samsung.com> wrote:
>> -----Original Message-----
>> From: Daniel Vetter [mailto:daniel.vetter@ffwll.ch]
>> Sent: Wednesday, August 07, 2013 6:15 PM
>> To: DRI Development
>> Cc: Intel Graphics Development; Daniel Vetter; Inki Dae
>> Subject: [PATCH 1/3] drm: use common drm_gem_dmabuf_release in i915/exynos
>> drivers
>>
>> Note that this is slightly tricky since both drivers store their
>> native objects in dma_buf->priv. But both also embed the base
>> drm_gem_object at the first position, so the implicit cast is ok.
>>
>> To use the release helper we need to export it, too.
>
> Yeah, may I repost this patch with additional work?  We also need to export
> with a gem object instead of specific one like you did.

I'm confused here what you mean, so pls just submit the patch. That
usually helps ;-)
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch

[PATCH 1/2] drm/i915: unpin backing storage in dmabuf_unmap

[Daniel Vetter]

This fixes a WARN in i915_gem_free_object when the
obj->pages_pin_count isn't 0.

v2: Add locking to unmap, noticed by Chris Wilson. Note that even
though we call unmap with our own dev->struct_mutex held that won't
result in an immediate deadlock since we never go through the dma_buf
interfaces for our own, reimported buffers. But it's still easy to
blow up and anger lockdep, but that's already the case with our ->map
implementation. Fixing this for real will involve per dma-buf ww mutex
locking by the callers. And lots of fun. So go with the duct-tape
approach for now.

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reported-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Tested-by: Armin K. <krejzi@email.com> (v1)
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
---
 drivers/gpu/drm/i915/i915_gem_dmabuf.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_gem_dmabuf.c b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
index 63ee1a9..f7e1682 100644
--- a/drivers/gpu/drm/i915/i915_gem_dmabuf.c
+++ b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
@@ -85,9 +85,17 @@ static void i915_gem_unmap_dma_buf(struct dma_buf_attachment *attachment,
 				   struct sg_table *sg,
 				   enum dma_data_direction dir)
 {
+	struct drm_i915_gem_object *obj = attachment->dmabuf->priv;
+
+	mutex_lock(&obj->base.dev->struct_mutex);
+
 	dma_unmap_sg(attachment->dev, sg->sgl, sg->nents, dir);
 	sg_free_table(sg);
 	kfree(sg);
+
+	i915_gem_object_unpin_pages(obj);
+
+	mutex_unlock(&obj->base.dev->struct_mutex);
 }
 
 static void *i915_gem_dmabuf_vmap(struct dma_buf *dma_buf)
-- 
1.8.3.2

[PATCH 2/2] drm/i915: no interruptible locking for dma_buf->map

[Daniel Vetter]

It's unclear whether ->map is allowed to fail with -EINTR, but
looking at current callers it's pretty clear that they don't
expect this to happen. So use a blocking mutex_lock call. Since
we don't wait for the gpu in our ->map callback the lack of the
gpu hang checks doesn't matter.

Furthermore the goal is to eventually have per dma-buf locking done
by callers with ww mutexes, so this will then be removed.

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
---
 drivers/gpu/drm/i915/i915_gem_dmabuf.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem_dmabuf.c b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
index f7e1682..63c0818 100644
--- a/drivers/gpu/drm/i915/i915_gem_dmabuf.c
+++ b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
@@ -35,9 +35,7 @@ static struct sg_table *i915_gem_map_dma_buf(struct dma_buf_attachment *attachme
 	struct scatterlist *src, *dst;
 	int ret, i;
 
-	ret = i915_mutex_lock_interruptible(obj->base.dev);
-	if (ret)
-		return ERR_PTR(ret);
+	mutex_lock(&obj->base.dev->struct_mutex);
 
 	ret = i915_gem_object_get_pages(obj);
 	if (ret) {
-- 
1.8.3.2

Re: [PATCH 1/3] drm: use common drm_gem_dmabuf_release in i915/exynos drivers

[Joonyoung Shim]

On 08/07/2013 06:55 PM, Daniel Vetter wrote:
> On Wed, Aug 7, 2013 at 11:40 AM, Inki Dae <inki.dae@samsung.com> wrote:
>>> -----Original Message-----
>>> From: Daniel Vetter [mailto:daniel.vetter@ffwll.ch]
>>> Sent: Wednesday, August 07, 2013 6:15 PM
>>> To: DRI Development
>>> Cc: Intel Graphics Development; Daniel Vetter; Inki Dae
>>> Subject: [PATCH 1/3] drm: use common drm_gem_dmabuf_release in i915/exynos
>>> drivers
>>>
>>> Note that this is slightly tricky since both drivers store their
>>> native objects in dma_buf->priv. But both also embed the base
>>> drm_gem_object at the first position, so the implicit cast is ok.
>>>
>>> To use the release helper we need to export it, too.
>> Yeah, may I repost this patch with additional work?  We also need to export
>> with a gem object instead of specific one like you did.

I think dmabuf stuff of exynos can be replaced to common drm_gem_dmabuf.
Already dmabuf stuff of drm_gem_cma_helper.c was substituted to common
drm_gem_dmabuf with low-level hook functions to use prime helpers.

Thanks.

> I'm confused here what you mean, so pls just submit the patch. That
> usually helps ;-)
> -Daniel

Re: [PATCH 1/3] drm: use common drm_gem_dmabuf_release in i915/exynos drivers

[Daniel Vetter]

On Wed, Aug 07, 2013 at 07:18:45PM +0900, Joonyoung Shim wrote:
> On 08/07/2013 06:55 PM, Daniel Vetter wrote:
> >On Wed, Aug 7, 2013 at 11:40 AM, Inki Dae <inki.dae@samsung.com> wrote:
> >>>-----Original Message-----
> >>>From: Daniel Vetter [mailto:daniel.vetter@ffwll.ch]
> >>>Sent: Wednesday, August 07, 2013 6:15 PM
> >>>To: DRI Development
> >>>Cc: Intel Graphics Development; Daniel Vetter; Inki Dae
> >>>Subject: [PATCH 1/3] drm: use common drm_gem_dmabuf_release in i915/exynos
> >>>drivers
> >>>
> >>>Note that this is slightly tricky since both drivers store their
> >>>native objects in dma_buf->priv. But both also embed the base
> >>>drm_gem_object at the first position, so the implicit cast is ok.
> >>>
> >>>To use the release helper we need to export it, too.
> >>Yeah, may I repost this patch with additional work?  We also need to export
> >>with a gem object instead of specific one like you did.
> 
> I think dmabuf stuff of exynos can be replaced to common drm_gem_dmabuf.
> Already dmabuf stuff of drm_gem_cma_helper.c was substituted to common
> drm_gem_dmabuf with low-level hook functions to use prime helpers.

Ah, but that can easily be done on top of this, right?
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch

Re: [PATCH 1/3] drm: use common drm_gem_dmabuf_release in i915/exynos drivers

[Joonyoung Shim]

On 08/07/2013 07:21 PM, Daniel Vetter wrote:
> On Wed, Aug 07, 2013 at 07:18:45PM +0900, Joonyoung Shim wrote:
>> On 08/07/2013 06:55 PM, Daniel Vetter wrote:
>>> On Wed, Aug 7, 2013 at 11:40 AM, Inki Dae <inki.dae@samsung.com> wrote:
>>>>> -----Original Message-----
>>>>> From: Daniel Vetter [mailto:daniel.vetter@ffwll.ch]
>>>>> Sent: Wednesday, August 07, 2013 6:15 PM
>>>>> To: DRI Development
>>>>> Cc: Intel Graphics Development; Daniel Vetter; Inki Dae
>>>>> Subject: [PATCH 1/3] drm: use common drm_gem_dmabuf_release in i915/exynos
>>>>> drivers
>>>>>
>>>>> Note that this is slightly tricky since both drivers store their
>>>>> native objects in dma_buf->priv. But both also embed the base
>>>>> drm_gem_object at the first position, so the implicit cast is ok.
>>>>>
>>>>> To use the release helper we need to export it, too.
>>>> Yeah, may I repost this patch with additional work?  We also need to export
>>>> with a gem object instead of specific one like you did.
>> I think dmabuf stuff of exynos can be replaced to common drm_gem_dmabuf.
>> Already dmabuf stuff of drm_gem_cma_helper.c was substituted to common
>> drm_gem_dmabuf with low-level hook functions to use prime helpers.
> Ah, but that can easily be done on top of this, right?
> -Daniel

I think it doesn't matter.

Re: [PATCH 2/2] drm/i915: no interruptible locking for dma_buf->map

[Chris Wilson]

On Wed, Aug 07, 2013 at 12:09:33PM +0200, Daniel Vetter wrote:
> It's unclear whether ->map is allowed to fail with -EINTR, but
> looking at current callers it's pretty clear that they don't
> expect this to happen. So use a blocking mutex_lock call. Since
> we don't wait for the gpu in our ->map callback the lack of the
> gpu hang checks doesn't matter.
> 
> Furthermore the goal is to eventually have per dma-buf locking done
> by callers with ww mutexes, so this will then be removed.
> 
> Cc: Chris Wilson <chris@chris-wilson.co.uk>
> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Ugh, who can't handle EINTR here but can handle all the other errors?
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre

Re: [PATCH 1/2] drm/i915: unpin backing storage in dmabuf_unmap

[Maarten Lankhorst]

Op 07-08-13 12:09, Daniel Vetter schreef:
> This fixes a WARN in i915_gem_free_object when the
> obj->pages_pin_count isn't 0.
>
> v2: Add locking to unmap, noticed by Chris Wilson. Note that even
> though we call unmap with our own dev->struct_mutex held that won't
> result in an immediate deadlock since we never go through the dma_buf
> interfaces for our own, reimported buffers. But it's still easy to
> blow up and anger lockdep, but that's already the case with our ->map
> implementation. Fixing this for real will involve per dma-buf ww mutex
> locking by the callers. And lots of fun. So go with the duct-tape
> approach for now.
>
> Cc: Chris Wilson <chris@chris-wilson.co.uk>
> Reported-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
> Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>
> Tested-by: Armin K. <krejzi@email.com> (v1)
> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
>
Acked, this was my original patch to solve the issue.

I want to note that locking struct_mutex here will break lockdep, but it's a problem in drm, not this patch.

~Maarten

Re: [PATCH 2/2] drm/i915: no interruptible locking for dma_buf->map

[Daniel Vetter]

On Wed, Aug 7, 2013 at 12:30 PM, Chris Wilson <chris@chris-wilson.co.uk> wrote:
> On Wed, Aug 07, 2013 at 12:09:33PM +0200, Daniel Vetter wrote:
>> It's unclear whether ->map is allowed to fail with -EINTR, but
>> looking at current callers it's pretty clear that they don't
>> expect this to happen. So use a blocking mutex_lock call. Since
>> we don't wait for the gpu in our ->map callback the lack of the
>> gpu hang checks doesn't matter.
>>
>> Furthermore the goal is to eventually have per dma-buf locking done
>> by callers with ww mutexes, so this will then be removed.
>>
>> Cc: Chris Wilson <chris@chris-wilson.co.uk>
>> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
>
> Ugh, who can't handle EINTR here but can handle all the other errors?

Ok, I've re-read the code and I think callers can actually cope. I'm
just freaked out that we don't have test coverage for these case, but
that should be a moot point once all the locking is converted over to
ww mutexes. So I'll drop this patch here.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch

Re: [PATCH 1/3] drm: use common drm_gem_dmabuf_release in i915/exynos drivers

[Inki Dae]

[-- Attachment #1.1: Type: text/plain, Size: 2397 bytes --]

2013/8/7 Daniel Vetter <daniel@ffwll.ch>

> On Wed, Aug 07, 2013 at 07:18:45PM +0900, Joonyoung Shim wrote:
> > On 08/07/2013 06:55 PM, Daniel Vetter wrote:
> > >On Wed, Aug 7, 2013 at 11:40 AM, Inki Dae <inki.dae@samsung.com> wrote:
> > >>>-----Original Message-----
> > >>>From: Daniel Vetter [mailto:daniel.vetter@ffwll.ch]
> > >>>Sent: Wednesday, August 07, 2013 6:15 PM
> > >>>To: DRI Development
> > >>>Cc: Intel Graphics Development; Daniel Vetter; Inki Dae
> > >>>Subject: [PATCH 1/3] drm: use common drm_gem_dmabuf_release in
> i915/exynos
> > >>>drivers
> > >>>
> > >>>Note that this is slightly tricky since both drivers store their
> > >>>native objects in dma_buf->priv. But both also embed the base
> > >>>drm_gem_object at the first position, so the implicit cast is ok.
> > >>>
> > >>>To use the release helper we need to export it, too.
> > >>Yeah, may I repost this patch with additional work?  We also need to
> export
> > >>with a gem object instead of specific one like you did.
> >
> > I think dmabuf stuff of exynos can be replaced to common drm_gem_dmabuf.
> > Already dmabuf stuff of drm_gem_cma_helper.c was substituted to common
> > drm_gem_dmabuf with low-level hook functions to use prime helpers.
>
> Ah, but that can easily be done on top of this, right?
>

Daniel, could you remove exynos related codes from your patch set?
Your patch set would make exynos broken because you didn't consider
exporting with a gem object for exynos like [PATCH 3/3] drm/i915: explicit
store base gem object in dma_buf->priv. So I think your patch set is not
complete set, and That is why exynos needs the additional work I mentioned
above. So I just wanted to repost your patch set + new one.
However, I think not only exynos could go to common drm_gem_dmabuf directly
but also it would make your patch set to be complete set if you remove
exynos related codes from your patch set. Otherwise, we have to work twice.
one is the additional work for resolving exynos broken issue by your patch
set, and other is to replace existing dmabuf stuff of exynos to common
drm_gem_dmabuf.

Thanks,
Inki Dae


> -Daniel
> --
> Daniel Vetter
> Software Engineer, Intel Corporation
> +41 (0) 79 365 57 48 - http://blog.ffwll.ch
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/dri-devel
>

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http://lists.freedesktop.org/mailman/listinfo/intel-gfx

Re: [PATCH 1/3] drm: use common drm_gem_dmabuf_release in i915/exynos drivers

[Daniel Vetter]

On Wed, Aug 7, 2013 at 2:01 PM, Inki Dae <inki.dae@samsung.com> wrote:
>
>
> 2013/8/7 Daniel Vetter <daniel@ffwll.ch>
>>
>> On Wed, Aug 07, 2013 at 07:18:45PM +0900, Joonyoung Shim wrote:
>> > On 08/07/2013 06:55 PM, Daniel Vetter wrote:
>> > >On Wed, Aug 7, 2013 at 11:40 AM, Inki Dae <inki.dae@samsung.com> wrote:
>> > >>>-----Original Message-----
>> > >>>From: Daniel Vetter [mailto:daniel.vetter@ffwll.ch]
>> > >>>Sent: Wednesday, August 07, 2013 6:15 PM
>> > >>>To: DRI Development
>> > >>>Cc: Intel Graphics Development; Daniel Vetter; Inki Dae
>> > >>>Subject: [PATCH 1/3] drm: use common drm_gem_dmabuf_release in
>> > >>> i915/exynos
>> > >>>drivers
>> > >>>
>> > >>>Note that this is slightly tricky since both drivers store their
>> > >>>native objects in dma_buf->priv. But both also embed the base
>> > >>>drm_gem_object at the first position, so the implicit cast is ok.
>> > >>>
>> > >>>To use the release helper we need to export it, too.
>> > >>Yeah, may I repost this patch with additional work?  We also need to
>> > >> export
>> > >>with a gem object instead of specific one like you did.
>> >
>> > I think dmabuf stuff of exynos can be replaced to common drm_gem_dmabuf.
>> > Already dmabuf stuff of drm_gem_cma_helper.c was substituted to common
>> > drm_gem_dmabuf with low-level hook functions to use prime helpers.
>>
>> Ah, but that can easily be done on top of this, right?
>
>
> Daniel, could you remove exynos related codes from your patch set? Your
> patch set would make exynos broken because you didn't consider exporting
> with a gem object for exynos like [PATCH 3/3] drm/i915: explicit store base
> gem object in dma_buf->priv. So I think your patch set is not complete set,
> and That is why exynos needs the additional work I mentioned above. So I
> just wanted to repost your patch set + new one.

Nope, my patch should not break exynos since the base gem_object is
the first member of the exynos object, so we don't have any issues
with upcasting in exynos dma-buf code. The same applies to i915
dma-buf code, my follow-up patch just makes the code a bit safer.

> However, I think not only exynos could go to common drm_gem_dmabuf directly
> but also it would make your patch set to be complete set if you remove
> exynos related codes from your patch set. Otherwise, we have to work twice.
> one is the additional work for resolving exynos broken issue by your patch
> set, and other is to replace existing dmabuf stuff of exynos to common
> drm_gem_dmabuf.

Yeah np, I'll drop exynos then.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch

Re: [PATCH 1/3] drm: use common drm_gem_dmabuf_release in i915/exynos drivers

[Inki Dae]

[-- Attachment #1.1: Type: text/plain, Size: 3082 bytes --]

2013/8/7 Daniel Vetter <daniel@ffwll.ch>

> On Wed, Aug 7, 2013 at 2:01 PM, Inki Dae <inki.dae@samsung.com> wrote:
> >
> >
> > 2013/8/7 Daniel Vetter <daniel@ffwll.ch>
> >>
> >> On Wed, Aug 07, 2013 at 07:18:45PM +0900, Joonyoung Shim wrote:
> >> > On 08/07/2013 06:55 PM, Daniel Vetter wrote:
> >> > >On Wed, Aug 7, 2013 at 11:40 AM, Inki Dae <inki.dae@samsung.com>
> wrote:
> >> > >>>-----Original Message-----
> >> > >>>From: Daniel Vetter [mailto:daniel.vetter@ffwll.ch]
> >> > >>>Sent: Wednesday, August 07, 2013 6:15 PM
> >> > >>>To: DRI Development
> >> > >>>Cc: Intel Graphics Development; Daniel Vetter; Inki Dae
> >> > >>>Subject: [PATCH 1/3] drm: use common drm_gem_dmabuf_release in
> >> > >>> i915/exynos
> >> > >>>drivers
> >> > >>>
> >> > >>>Note that this is slightly tricky since both drivers store their
> >> > >>>native objects in dma_buf->priv. But both also embed the base
> >> > >>>drm_gem_object at the first position, so the implicit cast is ok.
> >> > >>>
> >> > >>>To use the release helper we need to export it, too.
> >> > >>Yeah, may I repost this patch with additional work?  We also need to
> >> > >> export
> >> > >>with a gem object instead of specific one like you did.
> >> >
> >> > I think dmabuf stuff of exynos can be replaced to common
> drm_gem_dmabuf.
> >> > Already dmabuf stuff of drm_gem_cma_helper.c was substituted to common
> >> > drm_gem_dmabuf with low-level hook functions to use prime helpers.
> >>
> >> Ah, but that can easily be done on top of this, right?
> >
> >
> > Daniel, could you remove exynos related codes from your patch set? Your
> > patch set would make exynos broken because you didn't consider exporting
> > with a gem object for exynos like [PATCH 3/3] drm/i915: explicit store
> base
> > gem object in dma_buf->priv. So I think your patch set is not complete
> set,
> > and That is why exynos needs the additional work I mentioned above. So I
> > just wanted to repost your patch set + new one.
>
> Nope, my patch should not break exynos since the base gem_object is
> the first member of the exynos object, so we don't have any issues
>

Ah, right. However, it does not seem like good way.


> with upcasting in exynos dma-buf code. The same applies to i915
> dma-buf code, my follow-up patch just makes the code a bit safer.
>
>
>

>

>
> However, I think not only exynos could go to common drm_gem_dmabuf
> directly
> > but also it would make your patch set to be complete set if you remove
> > exynos related codes from your patch set. Otherwise, we have to work
> twice.
> > one is the additional work for resolving exynos broken issue by your
> patch
> > set, and other is to replace existing dmabuf stuff of exynos to common
> > drm_gem_dmabuf.
>
> Yeah np, I'll drop exynos then.
>

Thanks a lot. :)

Thanks,
Inki Dae


> -Daniel
> --
> Daniel Vetter
> Software Engineer, Intel Corporation
> +41 (0) 79 365 57 48 - http://blog.ffwll.ch
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/dri-devel
>

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Re: [PATCH 1/3] drm: use common drm_gem_dmabuf_release in i915/exynos drivers

[Daniel Vetter]

On Wed, Aug 07, 2013 at 09:37:52PM +0900, Inki Dae wrote:
> 2013/8/7 Daniel Vetter <daniel@ffwll.ch>
> 
> > On Wed, Aug 7, 2013 at 2:01 PM, Inki Dae <inki.dae@samsung.com> wrote:
> > >
> > >
> > > 2013/8/7 Daniel Vetter <daniel@ffwll.ch>
> > >>
> > >> On Wed, Aug 07, 2013 at 07:18:45PM +0900, Joonyoung Shim wrote:
> > >> > On 08/07/2013 06:55 PM, Daniel Vetter wrote:
> > >> > >On Wed, Aug 7, 2013 at 11:40 AM, Inki Dae <inki.dae@samsung.com>
> > wrote:
> > >> > >>>-----Original Message-----
> > >> > >>>From: Daniel Vetter [mailto:daniel.vetter@ffwll.ch]
> > >> > >>>Sent: Wednesday, August 07, 2013 6:15 PM
> > >> > >>>To: DRI Development
> > >> > >>>Cc: Intel Graphics Development; Daniel Vetter; Inki Dae
> > >> > >>>Subject: [PATCH 1/3] drm: use common drm_gem_dmabuf_release in
> > >> > >>> i915/exynos
> > >> > >>>drivers
> > >> > >>>
> > >> > >>>Note that this is slightly tricky since both drivers store their
> > >> > >>>native objects in dma_buf->priv. But both also embed the base
> > >> > >>>drm_gem_object at the first position, so the implicit cast is ok.
> > >> > >>>
> > >> > >>>To use the release helper we need to export it, too.
> > >> > >>Yeah, may I repost this patch with additional work?  We also need to
> > >> > >> export
> > >> > >>with a gem object instead of specific one like you did.
> > >> >
> > >> > I think dmabuf stuff of exynos can be replaced to common
> > drm_gem_dmabuf.
> > >> > Already dmabuf stuff of drm_gem_cma_helper.c was substituted to common
> > >> > drm_gem_dmabuf with low-level hook functions to use prime helpers.
> > >>
> > >> Ah, but that can easily be done on top of this, right?
> > >
> > >
> > > Daniel, could you remove exynos related codes from your patch set? Your
> > > patch set would make exynos broken because you didn't consider exporting
> > > with a gem object for exynos like [PATCH 3/3] drm/i915: explicit store
> > base
> > > gem object in dma_buf->priv. So I think your patch set is not complete
> > set,
> > > and That is why exynos needs the additional work I mentioned above. So I
> > > just wanted to repost your patch set + new one.
> >
> > Nope, my patch should not break exynos since the base gem_object is
> > the first member of the exynos object, so we don't have any issues
> >
> 
> Ah, right. However, it does not seem like good way.
> 
> 
> > with upcasting in exynos dma-buf code. The same applies to i915
> > dma-buf code, my follow-up patch just makes the code a bit safer.
> >
> >
> >
> 
> >
> 
> >
> > However, I think not only exynos could go to common drm_gem_dmabuf
> > directly
> > > but also it would make your patch set to be complete set if you remove
> > > exynos related codes from your patch set. Otherwise, we have to work
> > twice.
> > > one is the additional work for resolving exynos broken issue by your
> > patch
> > > set, and other is to replace existing dmabuf stuff of exynos to common
> > > drm_gem_dmabuf.
> >
> > Yeah np, I'll drop exynos then.
> >
> 
> Thanks a lot. :)

Ah, I remember again why I want to also convert over exynos to the common
dma buf release function: Later patches in my prime locking series will
change things in there to avoid a userspace-triggerable oops. If we leave
out exynos it'll break rather badly for dma-buf export.

I need to think a bit more about what stuff looks like atm, but if I
resend those parts I'll include exynos. It's a bit tricky that it still
works, but that way you can fix it up without the introduction of a bisect
failure point.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch

Re: [PATCH 1/2] drm/i915: unpin backing storage in dmabuf_unmap

[Konrad Rzeszutek Wilk]

On Wed, Aug 07, 2013 at 12:09:32PM +0200, Daniel Vetter wrote:
> This fixes a WARN in i915_gem_free_object when the
> obj->pages_pin_count isn't 0.
> 
> v2: Add locking to unmap, noticed by Chris Wilson. Note that even
> though we call unmap with our own dev->struct_mutex held that won't
> result in an immediate deadlock since we never go through the dma_buf
> interfaces for our own, reimported buffers. But it's still easy to
> blow up and anger lockdep, but that's already the case with our ->map
> implementation. Fixing this for real will involve per dma-buf ww mutex
> locking by the callers. And lots of fun. So go with the duct-tape
> approach for now.
> 
> Cc: Chris Wilson <chris@chris-wilson.co.uk>
> Reported-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
> Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>
> Tested-by: Armin K. <krejzi@email.com> (v1)
> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> ---
>  drivers/gpu/drm/i915/i915_gem_dmabuf.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/i915_gem_dmabuf.c b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
> index 63ee1a9..f7e1682 100644
> --- a/drivers/gpu/drm/i915/i915_gem_dmabuf.c
> +++ b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
> @@ -85,9 +85,17 @@ static void i915_gem_unmap_dma_buf(struct dma_buf_attachment *attachment,
>  				   struct sg_table *sg,
>  				   enum dma_data_direction dir)
>  {
> +	struct drm_i915_gem_object *obj = attachment->dmabuf->priv;
> +
> +	mutex_lock(&obj->base.dev->struct_mutex);
> +
>  	dma_unmap_sg(attachment->dev, sg->sgl, sg->nents, dir);
>  	sg_free_table(sg);
>  	kfree(sg);
> +
> +	i915_gem_object_unpin_pages(obj);

I am curious - would it logic of first unpinning, and then doing the dma_unmap_sg
make more sense? As in, in the map path we do:

dma_map
pin

And in here you do the same:

dma_unmap
unpin

But I would have thought that on a unroll you would do it in reverse
order, so:

unpin
dma_unmap

> +
> +	mutex_unlock(&obj->base.dev->struct_mutex);
>  }
>  
>  static void *i915_gem_dmabuf_vmap(struct dma_buf *dma_buf)
> -- 
> 1.8.3.2
> 
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: [PATCH 1/2] drm/i915: unpin backing storage in dmabuf_unmap

[Chris Wilson]

On Wed, Aug 07, 2013 at 08:50:20PM -0400, Konrad Rzeszutek Wilk wrote:
> On Wed, Aug 07, 2013 at 12:09:32PM +0200, Daniel Vetter wrote:
> > This fixes a WARN in i915_gem_free_object when the
> > obj->pages_pin_count isn't 0.
> > 
> > v2: Add locking to unmap, noticed by Chris Wilson. Note that even
> > though we call unmap with our own dev->struct_mutex held that won't
> > result in an immediate deadlock since we never go through the dma_buf
> > interfaces for our own, reimported buffers. But it's still easy to
> > blow up and anger lockdep, but that's already the case with our ->map
> > implementation. Fixing this for real will involve per dma-buf ww mutex
> > locking by the callers. And lots of fun. So go with the duct-tape
> > approach for now.
> > 
> > Cc: Chris Wilson <chris@chris-wilson.co.uk>
> > Reported-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
> > Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>
> > Tested-by: Armin K. <krejzi@email.com> (v1)
> > Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> > ---
> >  drivers/gpu/drm/i915/i915_gem_dmabuf.c | 8 ++++++++
> >  1 file changed, 8 insertions(+)
> > 
> > diff --git a/drivers/gpu/drm/i915/i915_gem_dmabuf.c b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
> > index 63ee1a9..f7e1682 100644
> > --- a/drivers/gpu/drm/i915/i915_gem_dmabuf.c
> > +++ b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
> > @@ -85,9 +85,17 @@ static void i915_gem_unmap_dma_buf(struct dma_buf_attachment *attachment,
> >  				   struct sg_table *sg,
> >  				   enum dma_data_direction dir)
> >  {
> > +	struct drm_i915_gem_object *obj = attachment->dmabuf->priv;
> > +
> > +	mutex_lock(&obj->base.dev->struct_mutex);
> > +
> >  	dma_unmap_sg(attachment->dev, sg->sgl, sg->nents, dir);
> >  	sg_free_table(sg);
> >  	kfree(sg);
> > +
> > +	i915_gem_object_unpin_pages(obj);
> 
> I am curious - would it logic of first unpinning, and then doing the dma_unmap_sg
> make more sense? As in, in the map path we do:
> 
> dma_map
> pin

Actually this is the wrong way around, and is a potential issue.
Hindsight is a powerful tool.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre

RE: [PATCH 1/3] drm: use common drm_gem_dmabuf_release in i915/exynos drivers

[Inki Dae]

> -----Original Message-----
> From: Daniel Vetter [mailto:daniel.vetter@ffwll.ch] On Behalf Of Daniel
> Vetter
> Sent: Thursday, August 08, 2013 8:21 AM
> To: Inki Dae
> Cc: Daniel Vetter; Intel Graphics Development; DRI Development
> Subject: Re: [PATCH 1/3] drm: use common drm_gem_dmabuf_release in
> i915/exynos drivers
> 
> On Wed, Aug 07, 2013 at 09:37:52PM +0900, Inki Dae wrote:
> > 2013/8/7 Daniel Vetter <daniel@ffwll.ch>
> >
> > > On Wed, Aug 7, 2013 at 2:01 PM, Inki Dae <inki.dae@samsung.com> wrote:
> > > >
> > > >
> > > > 2013/8/7 Daniel Vetter <daniel@ffwll.ch>
> > > >>
> > > >> On Wed, Aug 07, 2013 at 07:18:45PM +0900, Joonyoung Shim wrote:
> > > >> > On 08/07/2013 06:55 PM, Daniel Vetter wrote:
> > > >> > >On Wed, Aug 7, 2013 at 11:40 AM, Inki Dae <inki.dae@samsung.com>
> > > wrote:
> > > >> > >>>-----Original Message-----
> > > >> > >>>From: Daniel Vetter [mailto:daniel.vetter@ffwll.ch]
> > > >> > >>>Sent: Wednesday, August 07, 2013 6:15 PM
> > > >> > >>>To: DRI Development
> > > >> > >>>Cc: Intel Graphics Development; Daniel Vetter; Inki Dae
> > > >> > >>>Subject: [PATCH 1/3] drm: use common drm_gem_dmabuf_release in
> > > >> > >>> i915/exynos
> > > >> > >>>drivers
> > > >> > >>>
> > > >> > >>>Note that this is slightly tricky since both drivers store
> their
> > > >> > >>>native objects in dma_buf->priv. But both also embed the base
> > > >> > >>>drm_gem_object at the first position, so the implicit cast is
> ok.
> > > >> > >>>
> > > >> > >>>To use the release helper we need to export it, too.
> > > >> > >>Yeah, may I repost this patch with additional work?  We also
> need to
> > > >> > >> export
> > > >> > >>with a gem object instead of specific one like you did.
> > > >> >
> > > >> > I think dmabuf stuff of exynos can be replaced to common
> > > drm_gem_dmabuf.
> > > >> > Already dmabuf stuff of drm_gem_cma_helper.c was substituted to
> common
> > > >> > drm_gem_dmabuf with low-level hook functions to use prime
helpers.
> > > >>
> > > >> Ah, but that can easily be done on top of this, right?
> > > >
> > > >
> > > > Daniel, could you remove exynos related codes from your patch set?
> Your
> > > > patch set would make exynos broken because you didn't consider
> exporting
> > > > with a gem object for exynos like [PATCH 3/3] drm/i915: explicit
> store
> > > base
> > > > gem object in dma_buf->priv. So I think your patch set is not
> complete
> > > set,
> > > > and That is why exynos needs the additional work I mentioned above.
> So I
> > > > just wanted to repost your patch set + new one.
> > >
> > > Nope, my patch should not break exynos since the base gem_object is
> > > the first member of the exynos object, so we don't have any issues
> > >
> >
> > Ah, right. However, it does not seem like good way.
> >
> >
> > > with upcasting in exynos dma-buf code. The same applies to i915
> > > dma-buf code, my follow-up patch just makes the code a bit safer.
> > >
> > >
> > >
> >
> > >
> >
> > >
> > > However, I think not only exynos could go to common drm_gem_dmabuf
> > > directly
> > > > but also it would make your patch set to be complete set if you
> remove
> > > > exynos related codes from your patch set. Otherwise, we have to work
> > > twice.
> > > > one is the additional work for resolving exynos broken issue by your
> > > patch
> > > > set, and other is to replace existing dmabuf stuff of exynos to
> common
> > > > drm_gem_dmabuf.
> > >
> > > Yeah np, I'll drop exynos then.
> > >
> >
> > Thanks a lot. :)
> 
> Ah, I remember again why I want to also convert over exynos to the common
> dma buf release function: Later patches in my prime locking series will
> change things in there to avoid a userspace-triggerable oops. If we leave
> out exynos it'll break rather badly for dma-buf export.
> 
> I need to think a bit more about what stuff looks like atm, but if I
> resend those parts I'll include exynos. It's a bit tricky that it still
> works, but that way you can fix it up without the introduction of a bisect
> failure point.

I'll repost your patch set + new one that exports to a common gem object;
already worked and tested. I think it's good for they to be one set because
only using the patch 1/3 doesn't look good even though Exynos works fine
with the path 1/3.

So I'll repost it like below if you agree with me,
[PATCH 0/4] Small i915/exynos prime cleanup
[PATCH 1/4] drm: use common drm_gem_dmabuf_release in i915/exynos drivers
[PATCH 2/4] drm/i915: unpin backing storage in dmabuf_unmap
[PATCH 3/4] drm/i915: explicit store base gem object in dma_buf->priv
[PATCH 4/4] drm/exynos: explicit store base gem object in dma_buf->priv

After this, you can take care of them until merged to next. Or you can
repost this patch set including my patch again. What you proper doesn't
matter to me. :)

And it seems better that exynos keeps using existing dmabuf interfaces
without replacing them to common drm_gem_dmabuf ones because we may need
features only for Exynos. Actually, now exynos dmabuf includes some features
related to v4l2 and gpu driver for more performance.

Thanks,
Inki Dae

> -Daniel
> --
> Daniel Vetter
> Software Engineer, Intel Corporation
> +41 (0) 79 365 57 48 - http://blog.ffwll.ch

[PATCH 1/4] drm/exynos: explicit store base gem object in dma_buf->priv

[Inki Dae]

Signed-off-by: Inki Dae <inki.dae@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
---
 drivers/gpu/drm/exynos/exynos_drm_dmabuf.c |   12 ++++++++----
 1 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c b/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c
index 3cd56e1..fd76449 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c
@@ -22,6 +22,11 @@ struct exynos_drm_dmabuf_attachment {
 	bool is_mapped;
 };
 
+static struct exynos_drm_gem_obj *dma_buf_to_obj(struct dma_buf *buf)
+{
+	return to_exynos_gem_obj(buf->priv);
+}
+
 static int exynos_gem_attach_dma_buf(struct dma_buf *dmabuf,
 					struct device *dev,
 					struct dma_buf_attachment *attach)
@@ -63,7 +68,7 @@ static struct sg_table *
 					enum dma_data_direction dir)
 {
 	struct exynos_drm_dmabuf_attachment *exynos_attach = attach->priv;
-	struct exynos_drm_gem_obj *gem_obj = attach->dmabuf->priv;
+	struct exynos_drm_gem_obj *gem_obj = dma_buf_to_obj(attach->dmabuf);
 	struct drm_device *dev = gem_obj->base.dev;
 	struct exynos_drm_gem_buf *buf;
 	struct scatterlist *rd, *wr;
@@ -180,7 +185,7 @@ struct dma_buf *exynos_dmabuf_prime_export(struct drm_device *drm_dev,
 {
 	struct exynos_drm_gem_obj *exynos_gem_obj = to_exynos_gem_obj(obj);
 
-	return dma_buf_export(exynos_gem_obj, &exynos_dmabuf_ops,
+	return dma_buf_export(obj, &exynos_dmabuf_ops,
 				exynos_gem_obj->base.size, flags);
 }
 
@@ -198,8 +203,7 @@ struct drm_gem_object *exynos_dmabuf_prime_import(struct drm_device *drm_dev,
 	if (dma_buf->ops == &exynos_dmabuf_ops) {
 		struct drm_gem_object *obj;
 
-		exynos_gem_obj = dma_buf->priv;
-		obj = &exynos_gem_obj->base;
+		obj = dma_buf->priv;
 
 		/* is it from our device? */
 		if (obj->dev == drm_dev) {
-- 
1.7.5.4

RE: [PATCH 1/4] drm/exynos: explicit store base gem object in dma_buf->priv

[Inki Dae]

Hi, Daniel. You can repost your patch set including the below my patch. And
my patch numbering is wrong. Sorry about that.

[PATCH 1/4] -> [PATCH 4/4]


Thanks,
Inki Dae

> -----Original Message-----
> From: Inki Dae [mailto:inki.dae@samsung.com]
> Sent: Thursday, August 08, 2013 1:40 PM
> To: daniel@ffwll.ch
> Cc: dri-devel@lists.freedesktop.org; intel-gfx@lists.freedesktop.org; Inki
> Dae; Kyungmin Park
> Subject: [PATCH 1/4] drm/exynos: explicit store base gem object in
> dma_buf->priv
> 
> Signed-off-by: Inki Dae <inki.dae@samsung.com>
> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
> ---
>  drivers/gpu/drm/exynos/exynos_drm_dmabuf.c |   12 ++++++++----
>  1 files changed, 8 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c
> b/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c
> index 3cd56e1..fd76449 100644
> --- a/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c
> +++ b/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c
> @@ -22,6 +22,11 @@ struct exynos_drm_dmabuf_attachment {
>  	bool is_mapped;
>  };
> 
> +static struct exynos_drm_gem_obj *dma_buf_to_obj(struct dma_buf *buf)
> +{
> +	return to_exynos_gem_obj(buf->priv);
> +}
> +
>  static int exynos_gem_attach_dma_buf(struct dma_buf *dmabuf,
>  					struct device *dev,
>  					struct dma_buf_attachment *attach)
> @@ -63,7 +68,7 @@ static struct sg_table *
>  					enum dma_data_direction dir)
>  {
>  	struct exynos_drm_dmabuf_attachment *exynos_attach = attach->priv;
> -	struct exynos_drm_gem_obj *gem_obj = attach->dmabuf->priv;
> +	struct exynos_drm_gem_obj *gem_obj = dma_buf_to_obj(attach->dmabuf);
>  	struct drm_device *dev = gem_obj->base.dev;
>  	struct exynos_drm_gem_buf *buf;
>  	struct scatterlist *rd, *wr;
> @@ -180,7 +185,7 @@ struct dma_buf *exynos_dmabuf_prime_export(struct
> drm_device *drm_dev,
>  {
>  	struct exynos_drm_gem_obj *exynos_gem_obj = to_exynos_gem_obj(obj);
> 
> -	return dma_buf_export(exynos_gem_obj, &exynos_dmabuf_ops,
> +	return dma_buf_export(obj, &exynos_dmabuf_ops,
>  				exynos_gem_obj->base.size, flags);
>  }
> 
> @@ -198,8 +203,7 @@ struct drm_gem_object
> *exynos_dmabuf_prime_import(struct drm_device *drm_dev,
>  	if (dma_buf->ops == &exynos_dmabuf_ops) {
>  		struct drm_gem_object *obj;
> 
> -		exynos_gem_obj = dma_buf->priv;
> -		obj = &exynos_gem_obj->base;
> +		obj = dma_buf->priv;
> 
>  		/* is it from our device? */
>  		if (obj->dev == drm_dev) {
> --
> 1.7.5.4

Re: [PATCH 1/3] drm: use common drm_gem_dmabuf_release in i915/exynos drivers

[Daniel Vetter]

On Thu, Aug 8, 2013 at 6:32 AM, Inki Dae <inki.dae@samsung.com> wrote:
>
>
>> -----Original Message-----
>> From: Daniel Vetter [mailto:daniel.vetter@ffwll.ch] On Behalf Of Daniel
>> Vetter
>> Sent: Thursday, August 08, 2013 8:21 AM
>> To: Inki Dae
>> Cc: Daniel Vetter; Intel Graphics Development; DRI Development
>> Subject: Re: [PATCH 1/3] drm: use common drm_gem_dmabuf_release in
>> i915/exynos drivers
>>
>> On Wed, Aug 07, 2013 at 09:37:52PM +0900, Inki Dae wrote:
>> > 2013/8/7 Daniel Vetter <daniel@ffwll.ch>
>> >
>> > > On Wed, Aug 7, 2013 at 2:01 PM, Inki Dae <inki.dae@samsung.com> wrote:
>> > > >
>> > > >
>> > > > 2013/8/7 Daniel Vetter <daniel@ffwll.ch>
>> > > >>
>> > > >> On Wed, Aug 07, 2013 at 07:18:45PM +0900, Joonyoung Shim wrote:
>> > > >> > On 08/07/2013 06:55 PM, Daniel Vetter wrote:
>> > > >> > >On Wed, Aug 7, 2013 at 11:40 AM, Inki Dae <inki.dae@samsung.com>
>> > > wrote:
>> > > >> > >>>-----Original Message-----
>> > > >> > >>>From: Daniel Vetter [mailto:daniel.vetter@ffwll.ch]
>> > > >> > >>>Sent: Wednesday, August 07, 2013 6:15 PM
>> > > >> > >>>To: DRI Development
>> > > >> > >>>Cc: Intel Graphics Development; Daniel Vetter; Inki Dae
>> > > >> > >>>Subject: [PATCH 1/3] drm: use common drm_gem_dmabuf_release in
>> > > >> > >>> i915/exynos
>> > > >> > >>>drivers
>> > > >> > >>>
>> > > >> > >>>Note that this is slightly tricky since both drivers store
>> their
>> > > >> > >>>native objects in dma_buf->priv. But both also embed the base
>> > > >> > >>>drm_gem_object at the first position, so the implicit cast is
>> ok.
>> > > >> > >>>
>> > > >> > >>>To use the release helper we need to export it, too.
>> > > >> > >>Yeah, may I repost this patch with additional work?  We also
>> need to
>> > > >> > >> export
>> > > >> > >>with a gem object instead of specific one like you did.
>> > > >> >
>> > > >> > I think dmabuf stuff of exynos can be replaced to common
>> > > drm_gem_dmabuf.
>> > > >> > Already dmabuf stuff of drm_gem_cma_helper.c was substituted to
>> common
>> > > >> > drm_gem_dmabuf with low-level hook functions to use prime
> helpers.
>> > > >>
>> > > >> Ah, but that can easily be done on top of this, right?
>> > > >
>> > > >
>> > > > Daniel, could you remove exynos related codes from your patch set?
>> Your
>> > > > patch set would make exynos broken because you didn't consider
>> exporting
>> > > > with a gem object for exynos like [PATCH 3/3] drm/i915: explicit
>> store
>> > > base
>> > > > gem object in dma_buf->priv. So I think your patch set is not
>> complete
>> > > set,
>> > > > and That is why exynos needs the additional work I mentioned above.
>> So I
>> > > > just wanted to repost your patch set + new one.
>> > >
>> > > Nope, my patch should not break exynos since the base gem_object is
>> > > the first member of the exynos object, so we don't have any issues
>> > >
>> >
>> > Ah, right. However, it does not seem like good way.
>> >
>> >
>> > > with upcasting in exynos dma-buf code. The same applies to i915
>> > > dma-buf code, my follow-up patch just makes the code a bit safer.
>> > >
>> > >
>> > >
>> >
>> > >
>> >
>> > >
>> > > However, I think not only exynos could go to common drm_gem_dmabuf
>> > > directly
>> > > > but also it would make your patch set to be complete set if you
>> remove
>> > > > exynos related codes from your patch set. Otherwise, we have to work
>> > > twice.
>> > > > one is the additional work for resolving exynos broken issue by your
>> > > patch
>> > > > set, and other is to replace existing dmabuf stuff of exynos to
>> common
>> > > > drm_gem_dmabuf.
>> > >
>> > > Yeah np, I'll drop exynos then.
>> > >
>> >
>> > Thanks a lot. :)
>>
>> Ah, I remember again why I want to also convert over exynos to the common
>> dma buf release function: Later patches in my prime locking series will
>> change things in there to avoid a userspace-triggerable oops. If we leave
>> out exynos it'll break rather badly for dma-buf export.
>>
>> I need to think a bit more about what stuff looks like atm, but if I
>> resend those parts I'll include exynos. It's a bit tricky that it still
>> works, but that way you can fix it up without the introduction of a bisect
>> failure point.
>
> I'll repost your patch set + new one that exports to a common gem object;
> already worked and tested. I think it's good for they to be one set because
> only using the patch 1/3 doesn't look good even though Exynos works fine
> with the path 1/3.
>
> So I'll repost it like below if you agree with me,
> [PATCH 0/4] Small i915/exynos prime cleanup
> [PATCH 1/4] drm: use common drm_gem_dmabuf_release in i915/exynos drivers
> [PATCH 2/4] drm/i915: unpin backing storage in dmabuf_unmap
> [PATCH 3/4] drm/i915: explicit store base gem object in dma_buf->priv
> [PATCH 4/4] drm/exynos: explicit store base gem object in dma_buf->priv
>
> After this, you can take care of them until merged to next. Or you can
> repost this patch set including my patch again. What you proper doesn't
> matter to me. :)

Yeah, sounds like a plan. And I think those 4 patches can go in
earlier, the later patches I have need some more thought. Note that
the i915 patches have new versions meanwhile, so if you just submit
the exynos one I can integrate into my series.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch

Re: [PATCH 1/4] drm/exynos: explicit store base gem object in dma_buf->priv

[Daniel Vetter]

Hi Inki,

On Thu, Aug 08, 2013 at 01:56:28PM +0900, Inki Dae wrote:
> Hi, Daniel. You can repost your patch set including the below my patch. And
> my patch numbering is wrong. Sorry about that.

Thanks for the patch, I'll submit it toghether with the other ones soon.
-Daniel

> 
> [PATCH 1/4] -> [PATCH 4/4]
> 
> 
> Thanks,
> Inki Dae
> 
> > -----Original Message-----
> > From: Inki Dae [mailto:inki.dae@samsung.com]
> > Sent: Thursday, August 08, 2013 1:40 PM
> > To: daniel@ffwll.ch
> > Cc: dri-devel@lists.freedesktop.org; intel-gfx@lists.freedesktop.org; Inki
> > Dae; Kyungmin Park
> > Subject: [PATCH 1/4] drm/exynos: explicit store base gem object in
> > dma_buf->priv
> > 
> > Signed-off-by: Inki Dae <inki.dae@samsung.com>
> > Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
> > ---
> >  drivers/gpu/drm/exynos/exynos_drm_dmabuf.c |   12 ++++++++----
> >  1 files changed, 8 insertions(+), 4 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c
> > b/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c
> > index 3cd56e1..fd76449 100644
> > --- a/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c
> > +++ b/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c
> > @@ -22,6 +22,11 @@ struct exynos_drm_dmabuf_attachment {
> >  	bool is_mapped;
> >  };
> > 
> > +static struct exynos_drm_gem_obj *dma_buf_to_obj(struct dma_buf *buf)
> > +{
> > +	return to_exynos_gem_obj(buf->priv);
> > +}
> > +
> >  static int exynos_gem_attach_dma_buf(struct dma_buf *dmabuf,
> >  					struct device *dev,
> >  					struct dma_buf_attachment *attach)
> > @@ -63,7 +68,7 @@ static struct sg_table *
> >  					enum dma_data_direction dir)
> >  {
> >  	struct exynos_drm_dmabuf_attachment *exynos_attach = attach->priv;
> > -	struct exynos_drm_gem_obj *gem_obj = attach->dmabuf->priv;
> > +	struct exynos_drm_gem_obj *gem_obj = dma_buf_to_obj(attach->dmabuf);
> >  	struct drm_device *dev = gem_obj->base.dev;
> >  	struct exynos_drm_gem_buf *buf;
> >  	struct scatterlist *rd, *wr;
> > @@ -180,7 +185,7 @@ struct dma_buf *exynos_dmabuf_prime_export(struct
> > drm_device *drm_dev,
> >  {
> >  	struct exynos_drm_gem_obj *exynos_gem_obj = to_exynos_gem_obj(obj);
> > 
> > -	return dma_buf_export(exynos_gem_obj, &exynos_dmabuf_ops,
> > +	return dma_buf_export(obj, &exynos_dmabuf_ops,
> >  				exynos_gem_obj->base.size, flags);
> >  }
> > 
> > @@ -198,8 +203,7 @@ struct drm_gem_object
> > *exynos_dmabuf_prime_import(struct drm_device *drm_dev,
> >  	if (dma_buf->ops == &exynos_dmabuf_ops) {
> >  		struct drm_gem_object *obj;
> > 
> > -		exynos_gem_obj = dma_buf->priv;
> > -		obj = &exynos_gem_obj->base;
> > +		obj = dma_buf->priv;
> > 
> >  		/* is it from our device? */
> >  		if (obj->dev == drm_dev) {
> > --
> > 1.7.5.4
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch