vGEM buffers are useful for passing data between software clients and
hardware renders. By allowing the user to create and attach fences to
the exported vGEM buffers (on the dma-buf), the user can implement a
deferred renderer and queue hardware operations like flipping and then
signal the buffer readiness (i.e. this allows the user to schedule
operations out-of-order, but have them complete in-order).
This also makes it much easier to write tightly controlled testcases for
dma-buf fencing and signaling between hardware drivers.
v2: Don't pretend the fences exist in an ordered timeline, but allocate
a separate fence-context for each fence so that the fences are
unordered.
v3: Make the debug output more interesting, and show the signaled status.
v4: Automatically signal the fence to prevent userspace from
indefinitely hanging drivers.
Testcase: igt/vgem_basic/dmabuf-fence
Testcase: igt/vgem_slow/nohang
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: Zach Reizner <zachr@google.com>
Cc: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Zach Reizner <zachr@google.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1468571471-12610-1-git-send-email-chris@chris-wilson.co.uk
Currently enabling Nouveau DRM support automatically pulls in
fbdev dependency. However this dep is unnecessary since
DRM core already handles this for us (DRM_FBDEV_EMULATION).
Signed-off-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Currently enabling ATMEL HLCDC DRM support automatically pulls
in fbdev dependency. However this dep is unnecessary since
DRM core already handles this for us (DRM_FBDEV_EMULATION).
Signed-off-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Currently enabling R-Car DRM support automatically pulls in
fbdev dependency. However this dep is unnecessary since
DRM core already handles this for us (DRM_FBDEV_EMULATION).
Signed-off-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Currently enabling Rockchip DRM support automatically pulls
in fbdev dependency. However this dep is unnecessary since
DRM core already handles this for us (DRM_FBDEV_EMULATION).
Signed-off-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
of_node_put needs to be called when the device node which is got
from of_parse_phandle has finished using.
Cc: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
of_node_put needs to be called when the device node which is got
from of_parse_phandle has finished using.
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
of_node_put needs to be called when the device node which is got
from of_parse_phandle has finished using.
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Currently, we completely ignore the user when it comes to the in/out
direction of the ioctl argument, as we simply cannot trust userspace.
(For example, they might request a copy of the modified ioctl argument
when the driver is not expecting such and so leak kernel stack.)
However, blindly copying over the target address may also lead to a
spurious EFAULT, and a failure after the ioctl was completed
successfully. This is important in order to avoid an ABI break when
extending an ioctl from IOR to IORW. Similar to how we only copy the
intersection of the kernel arg size and the user arg size, we only want
to copy back the kernel arg data iff both the kernel and userspace
request the copy.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1468335590-21023-1-git-send-email-chris@chris-wilson.co.uk
Tobias Jakobi
Markus Elfring
Chris Wilson
Peter Chen
Daniel Vetter