Set vm_pgoff to 0 after using it to look up the GEM node, before passing it on rockchip_gem_mmap_buf() where the offset must be from the start of the buffer.
Passing in the fake offset currently works because the dma_mmap_attrs implementation that is used for this device, arm_iommu_mmap_attrs, ignores the offset completely.
Signed-off-by: Ørjan Eide orjan.eide@arm.com --- drivers/gpu/drm/rockchip/rockchip_drm_gem.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c index 7ca8799e..69f01c3 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c @@ -94,6 +94,11 @@ int rockchip_gem_mmap(struct file *filp, struct vm_area_struct *vma) return -EACCES; }
+ /* Set vm_pgoff (used as a fake buffer offset by DRM) to 0 and map the + * whole buffer from the start. + */ + vma->vm_pgoff = 0; + obj = container_of(node, struct drm_gem_object, vma_node); ret = rockchip_gem_mmap_buf(obj, vma);
arm_iommu_mmap_attrs() ignores the page offset in vma->vm_pgoff that was specified in the mmap call. Any user of dma_mmap_* will get an unexpected result when the device uses the IOMMU DMA ops.
Some DRM driver that use dma_mmap_* seems to depend on it ignoring vma->vm_pgoff. Both the Samsung Exynos DRM driver before v3.18, and the current Rockchip DRM driver, use the page offset to pass GEM cookies that are used to look up the GEM buffers and then call dma_mmap_attrs() with the cookie value still in vma->vm_pgoff.
rockchip_gem_mmap_buf() in drivers/gpu/drm/rockchip/rockchip_drm_gem.c still does this. It should be fixed before fixing arm_iommu_mmap_attrs().
Signed-off-by: Ørjan Eide orjan.eide@arm.com --- arch/arm/mm/dma-mapping.c | 8 ++++++++ 1 file changed, 8 insertions(+)
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index c274476..07d571b 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -1364,6 +1364,9 @@ static int arm_iommu_mmap_attrs(struct device *dev, struct vm_area_struct *vma, { unsigned long uaddr = vma->vm_start; unsigned long usize = vma->vm_end - vma->vm_start; + unsigned long nr_vma_pages = usize >> PAGE_SHIFT; + unsigned long nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT; + unsigned long off = vma->vm_pgoff; struct page **pages = __iommu_get_pages(cpu_addr, attrs);
vma->vm_page_prot = __get_dma_pgprot(attrs, vma->vm_page_prot); @@ -1371,6 +1374,11 @@ static int arm_iommu_mmap_attrs(struct device *dev, struct vm_area_struct *vma, if (!pages) return -ENXIO;
+ if (off >= nr_pages || nr_vma_pages > (nr_pages - off)) + return -ENXIO; + + pages += off; + do { int ret = vm_insert_page(vma, uaddr, *pages++); if (ret) {
Hi Ørjan,
On Thu, Apr 16, 2015 at 10:41 PM, Ørjan Eide orjan.eide@arm.com wrote:
arm_iommu_mmap_attrs() ignores the page offset in vma->vm_pgoff that was specified in the mmap call. Any user of dma_mmap_* will get an unexpected result when the device uses the IOMMU DMA ops.
Some DRM driver that use dma_mmap_* seems to depend on it ignoring vma->vm_pgoff. Both the Samsung Exynos DRM driver before v3.18, and the current Rockchip DRM driver, use the page offset to pass GEM cookies that are used to look up the GEM buffers and then call dma_mmap_attrs() with the cookie value still in vma->vm_pgoff.
rockchip_gem_mmap_buf() in drivers/gpu/drm/rockchip/rockchip_drm_gem.c still does this. It should be fixed before fixing arm_iommu_mmap_attrs().
Signed-off-by: Ørjan Eide orjan.eide@arm.com
Reviewed-by: Daniel Kurtz djkurtz@chromium.org
I tested this patch on my RK3288 board with the corresponding rockchip_drm patch [0], and it works. So, also: Tested-by: Daniel Kurtz djkurtz@chromium.org
[0] https://patchwork.kernel.org/patch/6226591/
arch/arm/mm/dma-mapping.c | 8 ++++++++ 1 file changed, 8 insertions(+)
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index c274476..07d571b 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -1364,6 +1364,9 @@ static int arm_iommu_mmap_attrs(struct device *dev, struct vm_area_struct *vma, { unsigned long uaddr = vma->vm_start; unsigned long usize = vma->vm_end - vma->vm_start;
unsigned long nr_vma_pages = usize >> PAGE_SHIFT;unsigned long nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT;unsigned long off = vma->vm_pgoff; struct page **pages = __iommu_get_pages(cpu_addr, attrs); vma->vm_page_prot = __get_dma_pgprot(attrs, vma->vm_page_prot);@@ -1371,6 +1374,11 @@ static int arm_iommu_mmap_attrs(struct device *dev, struct vm_area_struct *vma, if (!pages) return -ENXIO;
if (off >= nr_pages || nr_vma_pages > (nr_pages - off))return -ENXIO;pages += off;do { int ret = vm_insert_page(vma, uaddr, *pages++); if (ret) {-- 1.9.1
Am Donnerstag, 16. April 2015, 16:41:51 schrieb Ørjan Eide:
Set vm_pgoff to 0 after using it to look up the GEM node, before passing it on rockchip_gem_mmap_buf() where the offset must be from the start of the buffer.
Passing in the fake offset currently works because the dma_mmap_attrs implementation that is used for this device, arm_iommu_mmap_attrs, ignores the offset completely.
Signed-off-by: Ørjan Eide orjan.eide@arm.com
both patches on a rk3288-veyron-pinky
Tested-by: Heiko Stuebner heiko@sntech.de
Through which tree do you want to take these patches? I guess the rockchip-drm related patch should go through the tree that will take the dma-mapping patch, so you'll probably need an "Ack" from Mark Yao (Cc'ed).
Heiko
drivers/gpu/drm/rockchip/rockchip_drm_gem.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c index 7ca8799e..69f01c3 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c @@ -94,6 +94,11 @@ int rockchip_gem_mmap(struct file *filp, struct vm_area_struct *vma) return -EACCES; }
- /* Set vm_pgoff (used as a fake buffer offset by DRM) to 0 and map the
* whole buffer from the start.*/- vma->vm_pgoff = 0;
- obj = container_of(node, struct drm_gem_object, vma_node); ret = rockchip_gem_mmap_buf(obj, vma);
On 2015年04月19日 00:55, Heiko Stübner wrote:
Am Donnerstag, 16. April 2015, 16:41:51 schrieb Ørjan Eide:
Set vm_pgoff to 0 after using it to look up the GEM node, before passing it on rockchip_gem_mmap_buf() where the offset must be from the start of the buffer.
Passing in the fake offset currently works because the dma_mmap_attrs implementation that is used for this device, arm_iommu_mmap_attrs, ignores the offset completely.
Signed-off-by: Ørjan Eide orjan.eide@arm.com
both patches on a rk3288-veyron-pinky
Tested-by: Heiko Stuebner heiko@sntech.de
Through which tree do you want to take these patches? I guess the rockchip-drm related patch should go through the tree that will take the dma-mapping patch, so you'll probably need an "Ack" from Mark Yao (Cc'ed).
Heiko
drivers/gpu/drm/rockchip/rockchip_drm_gem.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c index 7ca8799e..69f01c3 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c @@ -94,6 +94,11 @@ int rockchip_gem_mmap(struct file *filp, struct vm_area_struct *vma) return -EACCES; }
- /* Set vm_pgoff (used as a fake buffer offset by DRM) to 0 and map the
* whole buffer from the start.*/- vma->vm_pgoff = 0;
- obj = container_of(node, struct drm_gem_object, vma_node); ret = rockchip_gem_mmap_buf(obj, vma);
Thanks for this fix, Acked-by: Mark Yao mark.yao@rock-chips.com
On 2015年04月20日 13:34, Mark yao wrote:
On 2015年04月19日 00:55, Heiko Stübner wrote:
Am Donnerstag, 16. April 2015, 16:41:51 schrieb Ørjan Eide:
Set vm_pgoff to 0 after using it to look up the GEM node, before passing it on rockchip_gem_mmap_buf() where the offset must be from the start of the buffer.
Passing in the fake offset currently works because the dma_mmap_attrs implementation that is used for this device, arm_iommu_mmap_attrs, ignores the offset completely.
Signed-off-by: Ørjan Eide orjan.eide@arm.com
both patches on a rk3288-veyron-pinky
Tested-by: Heiko Stuebner heiko@sntech.de
Through which tree do you want to take these patches? I guess the rockchip-drm related patch should go through the tree that will take the dma-mapping patch, so you'll probably need an "Ack" from Mark Yao (Cc'ed).
Heiko
drivers/gpu/drm/rockchip/rockchip_drm_gem.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c index 7ca8799e..69f01c3 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c @@ -94,6 +94,11 @@ int rockchip_gem_mmap(struct file *filp, struct vm_area_struct *vma) return -EACCES; }
- /* Set vm_pgoff (used as a fake buffer offset by DRM) to 0 and
map the
* whole buffer from the start.*/- vma->vm_pgoff = 0;
obj = container_of(node, struct drm_gem_object, vma_node); ret = rockchip_gem_mmap_buf(obj, vma);Thanks for this fix, Acked-by: Mark Yao mark.yao@rock-chips.com
I met this problem when work with gem non-iommu path, set vma->vm_pgoff = 0 solved it. :-)
On Sun, Apr 19, 2015 at 12:55 AM, Heiko Stübner heiko@sntech.de wrote:
Am Donnerstag, 16. April 2015, 16:41:51 schrieb Ørjan Eide:
Set vm_pgoff to 0 after using it to look up the GEM node, before passing it on rockchip_gem_mmap_buf() where the offset must be from the start of the buffer.
Passing in the fake offset currently works because the dma_mmap_attrs implementation that is used for this device, arm_iommu_mmap_attrs, ignores the offset completely.
Signed-off-by: Ørjan Eide orjan.eide@arm.com
both patches on a rk3288-veyron-pinky
Tested-by: Heiko Stuebner heiko@sntech.de
Through which tree do you want to take these patches? I guess the rockchip-drm related patch should go through the tree that will take the dma-mapping patch, so you'll probably need an "Ack" from Mark Yao (Cc'ed).
As far as I can tell, these two patches ([0] & [1]) were never picked up. Russell, can you pick both of them up in your tree?
[0] https://patchwork.kernel.org/patch/6226591/ [1] https://patchwork.kernel.org/patch/6226581/
-Dan
Heiko
drivers/gpu/drm/rockchip/rockchip_drm_gem.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c index 7ca8799e..69f01c3 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c @@ -94,6 +94,11 @@ int rockchip_gem_mmap(struct file *filp, struct vm_area_struct *vma) return -EACCES; }
/* Set vm_pgoff (used as a fake buffer offset by DRM) to 0 and map the* whole buffer from the start.*/vma->vm_pgoff = 0;obj = container_of(node, struct drm_gem_object, vma_node); ret = rockchip_gem_mmap_buf(obj, vma);
Hi Ørjan,
On Thu, Apr 16, 2015 at 10:41 PM, Ørjan Eide orjan.eide@arm.com wrote:
Set vm_pgoff to 0 after using it to look up the GEM node, before passing it on rockchip_gem_mmap_buf() where the offset must be from the start of the buffer.
Passing in the fake offset currently works because the dma_mmap_attrs implementation that is used for this device, arm_iommu_mmap_attrs, ignores the offset completely.
Signed-off-by: Ørjan Eide orjan.eide@arm.com
drivers/gpu/drm/rockchip/rockchip_drm_gem.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c index 7ca8799e..69f01c3 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c @@ -94,6 +94,11 @@ int rockchip_gem_mmap(struct file *filp, struct vm_area_struct *vma) return -EACCES; }
/* Set vm_pgoff (used as a fake buffer offset by DRM) to 0 and map the* whole buffer from the start.*/
One very tiny nit. According to [0], multi-line comments start are supposed to start with a single "/*" [0] https://www.kernel.org/doc/Documentation/CodingStyle
Other than that, this patch is Reviewed-by: Daniel Kurtz djkurtz@chromium.org
Thanks for sending this up!
vma->vm_pgoff = 0;obj = container_of(node, struct drm_gem_object, vma_node); ret = rockchip_gem_mmap_buf(obj, vma);-- 1.9.1
dri-devel@lists.freedesktop.org
-
Daniel Kurtz -
Heiko Stübner -
Mark yao -
Ørjan Eide