From: Gustavo Padovan <[email protected]>
Hi,
Another iteration after Brian comments. Please refer to the cover letter[1] in
a previous version to check for more details.
The changes since the last version can be seen in commit message on each patch.
Robert Foss managed to port Android's drm_hwcomposer to the new HWC2 API and
added support to fences. Current patches can be seen here:
https://git.collabora.com/cgit/user/robertfoss/drm_hwcomposer.git/log/?h=hwc2_fence_v1
He ran AOSP on top of padovan/fences kernel branch with full fence support on
qemu/virgl and msm db410c. That means we already have a working open source
userspace using the explicit fencing implementation.
Also i-g-t testing are available with all tests suggested in v7 included:
https://git.collabora.com/cgit/user/padovan/intel-gpu-tools.git/log/
Please review!
Gustavo
[1] https://www.mail-archive.com/[email protected]/msg1253822.html
---
Gustavo Padovan (3):
drm/fence: add in-fences support
drm/fence: add fence timeline to drm_crtc
drm/fence: add out-fences support
drivers/gpu/drm/Kconfig | 1 +
drivers/gpu/drm/drm_atomic.c | 257 +++++++++++++++++++++++++++++-------
drivers/gpu/drm/drm_atomic_helper.c | 5 +
drivers/gpu/drm/drm_crtc.c | 45 +++++++
drivers/gpu/drm/drm_plane.c | 1 +
include/drm/drm_atomic.h | 1 +
include/drm/drm_crtc.h | 56 ++++++++
7 files changed, 321 insertions(+), 45 deletions(-)
--
2.5.5
From: Gustavo Padovan <[email protected]>
There is now a new property called IN_FENCE_FD attached to every plane
state that receives sync_file fds from userspace via the atomic commit
IOCTL.
The fd is then translated to a fence (that may be a fence_array
subclass or just a normal fence) and then used by DRM to fence_wait() for
all fences in the sync_file to signal. So it only commits when all
framebuffers are ready to scanout.
v2: Comments by Daniel Vetter:
- remove set state->fence = NULL in destroy phase
- accept fence -1 as valid and just return 0
- do not call fence_get() - sync_file_fences_get() already calls it
- fence_put() if state->fence is already set, in case userspace
set the property more than once.
v3: WARN_ON if fence is set but state has no FB
v4: Comment from Maarten Lankhorst
- allow set fence with no related fb
v5: rename FENCE_FD to IN_FENCE_FD
v6: Comments by Daniel Vetter:
- rename plane_state->in_fence back to "fence"
- re-introduce WARN_ON if fence set but no fb
- rebase after fence -> dma_fence rename
v7: Comments by Brian Starkey
- set state->fence to NULL when duplicating the state
- fail if IN_FENCE_FD was already set
Signed-off-by: Gustavo Padovan <[email protected]>
Reviewed-by: Brian Starkey <[email protected]>
---
drivers/gpu/drm/Kconfig | 1 +
drivers/gpu/drm/drm_atomic.c | 14 ++++++++++++++
drivers/gpu/drm/drm_atomic_helper.c | 5 +++++
drivers/gpu/drm/drm_crtc.c | 6 ++++++
drivers/gpu/drm/drm_plane.c | 1 +
include/drm/drm_crtc.h | 5 +++++
6 files changed, 32 insertions(+)
diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
index 25e8e37..360cb92 100644
--- a/drivers/gpu/drm/Kconfig
+++ b/drivers/gpu/drm/Kconfig
@@ -12,6 +12,7 @@ menuconfig DRM
select I2C
select I2C_ALGOBIT
select DMA_SHARED_BUFFER
+ select SYNC_FILE
help
Kernel-level support for the Direct Rendering Infrastructure (DRI)
introduced in XFree86 4.0. If you say Y here, you need to select
diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index b096c16..8e26ad1 100644
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -31,6 +31,7 @@
#include <drm/drm_mode.h>
#include <drm/drm_plane_helper.h>
#include <drm/drm_print.h>
+#include <linux/sync_file.h>
#include "drm_crtc_internal.h"
@@ -709,6 +710,17 @@ int drm_atomic_plane_set_property(struct drm_plane *plane,
drm_atomic_set_fb_for_plane(state, fb);
if (fb)
drm_framebuffer_unreference(fb);
+ } else if (property == config->prop_in_fence_fd) {
+ if (state->fence)
+ return -EINVAL;
+
+ if (U642I64(val) == -1)
+ return 0;
+
+ state->fence = sync_file_get_fence(val);
+ if (!state->fence)
+ return -EINVAL;
+
} else if (property == config->prop_crtc_id) {
struct drm_crtc *crtc = drm_crtc_find(dev, val);
return drm_atomic_set_crtc_for_plane(state, crtc);
@@ -770,6 +782,8 @@ drm_atomic_plane_get_property(struct drm_plane *plane,
if (property == config->prop_fb_id) {
*val = (state->fb) ? state->fb->base.id : 0;
+ } else if (property == config->prop_in_fence_fd) {
+ *val = -1;
} else if (property == config->prop_crtc_id) {
*val = (state->crtc) ? state->crtc->base.id : 0;
} else if (property == config->prop_crtc_x) {
diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index 75ad01d..caed870 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -3076,6 +3076,8 @@ void __drm_atomic_helper_plane_duplicate_state(struct drm_plane *plane,
if (state->fb)
drm_framebuffer_reference(state->fb);
+
+ state->fence = NULL;
}
EXPORT_SYMBOL(__drm_atomic_helper_plane_duplicate_state);
@@ -3114,6 +3116,9 @@ void __drm_atomic_helper_plane_destroy_state(struct drm_plane_state *state)
{
if (state->fb)
drm_framebuffer_unreference(state->fb);
+
+ if (state->fence)
+ dma_fence_put(state->fence);
}
EXPORT_SYMBOL(__drm_atomic_helper_plane_destroy_state);
diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index ce274ed..154e040 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -397,6 +397,12 @@ static int drm_mode_create_standard_properties(struct drm_device *dev)
return -ENOMEM;
dev->mode_config.prop_fb_id = prop;
+ prop = drm_property_create_signed_range(dev, DRM_MODE_PROP_ATOMIC,
+ "IN_FENCE_FD", -1, INT_MAX);
+ if (!prop)
+ return -ENOMEM;
+ dev->mode_config.prop_in_fence_fd = prop;
+
prop = drm_property_create_object(dev, DRM_MODE_PROP_ATOMIC,
"CRTC_ID", DRM_MODE_OBJECT_CRTC);
if (!prop)
diff --git a/drivers/gpu/drm/drm_plane.c b/drivers/gpu/drm/drm_plane.c
index 249c0ae..3957ef8 100644
--- a/drivers/gpu/drm/drm_plane.c
+++ b/drivers/gpu/drm/drm_plane.c
@@ -137,6 +137,7 @@ int drm_universal_plane_init(struct drm_device *dev, struct drm_plane *plane,
if (drm_core_check_feature(dev, DRIVER_ATOMIC)) {
drm_object_attach_property(&plane->base, config->prop_fb_id, 0);
+ drm_object_attach_property(&plane->base, config->prop_in_fence_fd, -1);
drm_object_attach_property(&plane->base, config->prop_crtc_id, 0);
drm_object_attach_property(&plane->base, config->prop_crtc_x, 0);
drm_object_attach_property(&plane->base, config->prop_crtc_y, 0);
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 8cca2a8..11780a9 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -1214,6 +1214,11 @@ struct drm_mode_config {
*/
struct drm_property *prop_fb_id;
/**
+ * @prop_in_fence_fd: Sync File fd representing the incoming fences
+ * for a Plane.
+ */
+ struct drm_property *prop_in_fence_fd;
+ /**
* @prop_crtc_id: Default atomic plane property to specify the
* &drm_crtc.
*/
--
2.5.5
From: Gustavo Padovan <[email protected]>
Create one timeline context for each CRTC to be able to handle out-fences
and signal them. It adds a few members to struct drm_crtc: fence_context,
where we store the context we get from fence_context_alloc(), the
fence seqno and the fence lock, that we pass in fence_init() to be
used by the fence.
v2: Comment by Daniel Stone:
- add BUG_ON() to fence_to_crtc() macro
v3: Comment by Ville Syrjälä
- Use more meaningful name as crtc timeline name
v4: Comments by Brian Starkey
- Use even more meaninful name for the crtc timeline
- add doc for timeline_name
Comment by Daniel Vetter
- use in-line style for comments
- rebase after fence -> dma_fence rename
v5: Comment by Daniel Vetter
- Add doc for drm_crtc_fence_ops
Signed-off-by: Gustavo Padovan <[email protected]>
Reviewed-by: Daniel Vetter <[email protected]>
---
drivers/gpu/drm/drm_crtc.c | 31 +++++++++++++++++++++++++++++++
include/drm/drm_crtc.h | 45 +++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 76 insertions(+)
diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index 154e040..9b9881b 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -165,6 +165,32 @@ static void drm_crtc_crc_fini(struct drm_crtc *crtc)
#endif
}
+static const char *drm_crtc_fence_get_driver_name(struct dma_fence *fence)
+{
+ struct drm_crtc *crtc = fence_to_crtc(fence);
+
+ return crtc->dev->driver->name;
+}
+
+static const char *drm_crtc_fence_get_timeline_name(struct dma_fence *fence)
+{
+ struct drm_crtc *crtc = fence_to_crtc(fence);
+
+ return crtc->timeline_name;
+}
+
+static bool drm_crtc_fence_enable_signaling(struct dma_fence *fence)
+{
+ return true;
+}
+
+const struct dma_fence_ops drm_crtc_fence_ops = {
+ .get_driver_name = drm_crtc_fence_get_driver_name,
+ .get_timeline_name = drm_crtc_fence_get_timeline_name,
+ .enable_signaling = drm_crtc_fence_enable_signaling,
+ .wait = dma_fence_default_wait,
+};
+
/**
* drm_crtc_init_with_planes - Initialise a new CRTC object with
* specified primary and cursor planes.
@@ -222,6 +248,11 @@ int drm_crtc_init_with_planes(struct drm_device *dev, struct drm_crtc *crtc,
return -ENOMEM;
}
+ crtc->fence_context = dma_fence_context_alloc(1);
+ spin_lock_init(&crtc->fence_lock);
+ snprintf(crtc->timeline_name, sizeof(crtc->timeline_name),
+ "CRTC:%d-%s", crtc->base.id, crtc->name);
+
crtc->base.properties = &crtc->properties;
list_add_tail(&crtc->head, &config->crtc_list);
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 11780a9..0870de1 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -32,6 +32,8 @@
#include <linux/fb.h>
#include <linux/hdmi.h>
#include <linux/media-bus-format.h>
+#include <linux/srcu.h>
+#include <linux/dma-fence.h>
#include <uapi/drm/drm_mode.h>
#include <uapi/drm/drm_fourcc.h>
#include <drm/drm_modeset_lock.h>
@@ -739,9 +741,52 @@ struct drm_crtc {
*/
struct drm_crtc_crc crc;
#endif
+
+ /**
+ * @fence_context:
+ *
+ * timeline context used for fence operations.
+ */
+ unsigned int fence_context;
+
+ /**
+ * @fence_lock:
+ *
+ * spinlock to protect the fences in the fence_context.
+ */
+
+ spinlock_t fence_lock;
+ /**
+ * @fence_seqno:
+ *
+ * Seqno variable used as monotonic counter for the fences
+ * created on the CRTC's timeline.
+ */
+ unsigned long fence_seqno;
+
+ /**
+ * @timeline_name:
+ *
+ * The name of the CRTC's fence timeline.
+ */
+ char timeline_name[32];
};
/**
+ * dma_crtc_fence_ops - fence ops for the drm_crtc timeline
+ *
+ * It contains the dma_fence_ops that should be called by the dma_fence
+ * code. CRTC core should use this ops when initializing fences.
+ */
+extern const struct dma_fence_ops drm_crtc_fence_ops;
+
+static inline struct drm_crtc *fence_to_crtc(struct dma_fence *fence)
+{
+ BUG_ON(fence->ops != &drm_crtc_fence_ops);
+ return container_of(fence->lock, struct drm_crtc, fence_lock);
+}
+
+/**
* struct drm_mode_set - new values for a CRTC config change
* @fb: framebuffer to use for new config
* @crtc: CRTC whose configuration we're about to change
--
2.5.5
From: Gustavo Padovan <[email protected]>
Support DRM out-fences by creating a sync_file with a fence for each CRTC
that sets the OUT_FENCE_PTR property.
We use the out_fence pointer received in the OUT_FENCE_PTR prop to send
the sync_file fd back to userspace.
The sync_file and fd are allocated/created before commit, but the
fd_install operation only happens after we know that commit succeed.
v2: Comment by Rob Clark:
- Squash commit that adds DRM_MODE_ATOMIC_OUT_FENCE flag here.
Comment by Daniel Vetter:
- Add clean up code for out_fences
v3: Comments by Daniel Vetter:
- create DRM_MODE_ATOMIC_EVENT_MASK
- userspace should fill out_fences_ptr with the crtc_ids for which
it wants fences back.
v4: Create OUT_FENCE_PTR properties and remove old approach.
v5: Comments by Brian Starkey:
- Remove extra fence_get() in atomic_ioctl()
- Check ret before iterating on the crtc_state
- check ret before fd_install
- set fence_state to NULL at the beginning
- check fence_state->out_fence_ptr before put_user()
- change order of fput() and put_unused_fd() on failure
- Add access_ok() check to the out_fence_ptr received
- Rebase after fence -> dma_fence rename
- Store out_fence_ptr in the drm_atomic_state
- Split crtc_setup_out_fence()
- return -1 as out_fence with TEST_ONLY flag
v6: Comments by Daniel Vetter
- Add prepare/unprepare_crtc_signaling()
- move struct drm_out_fence_state to drm_atomic.c
- mark get_crtc_fence() as static
Comments by Brian Starkey
- proper set fence_ptr fence_state array
- isolate fence_idx increment
- improve error handling
v7: Comments by Daniel Vetter
- remove prefix from internal functions
- make out_fence_ptr an s64 pointer
- degrade DRM_INFO to DRM_DEBUG_ATOMIC when put_user fail
- fix doc issues
- filter out OUT_FENCE_PTR == NULL and do not fail in this case
- add complete_crtc_signalling()
- krealloc fence_state on demand
Comment by Brian Starkey
- remove unused crtc_state arg from get_out_fence()
v8: Comment by Brian Starkey
- cancel events before check for !fence_state
- convert a few lefovers u64 types for out_fence_ptr
- fix memleak by assign fence_state earlier after realloc
- proper accout num_fences in case of error
Signed-off-by: Gustavo Padovan <[email protected]>
---
drivers/gpu/drm/drm_atomic.c | 243 +++++++++++++++++++++++++++++++++++--------
drivers/gpu/drm/drm_crtc.c | 8 ++
include/drm/drm_atomic.h | 1 +
include/drm/drm_crtc.h | 6 ++
4 files changed, 213 insertions(+), 45 deletions(-)
diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index 8e26ad1..34cdc6e 100644
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -290,6 +290,23 @@ drm_atomic_get_crtc_state(struct drm_atomic_state *state,
}
EXPORT_SYMBOL(drm_atomic_get_crtc_state);
+static void set_out_fence_for_crtc(struct drm_atomic_state *state,
+ struct drm_crtc *crtc, s64 __user *fence_ptr)
+{
+ state->crtcs[drm_crtc_index(crtc)].out_fence_ptr = fence_ptr;
+}
+
+static s64 __user * get_out_fence_for_crtc(struct drm_atomic_state *state,
+ struct drm_crtc *crtc)
+{
+ s64 __user *fence_ptr;
+
+ fence_ptr = state->crtcs[drm_crtc_index(crtc)].out_fence_ptr;
+ state->crtcs[drm_crtc_index(crtc)].out_fence_ptr = NULL;
+
+ return fence_ptr;
+}
+
/**
* drm_atomic_set_mode_for_crtc - set mode for CRTC
* @state: the CRTC whose incoming state to update
@@ -491,6 +508,16 @@ int drm_atomic_crtc_set_property(struct drm_crtc *crtc,
&replaced);
state->color_mgmt_changed |= replaced;
return ret;
+ } else if (property == config->prop_out_fence_ptr) {
+ s64 __user *fence_ptr = u64_to_user_ptr(val);
+
+ if (!fence_ptr)
+ return 0;
+
+ if (!access_ok(VERIFY_WRITE, fence_ptr, sizeof(*fence_ptr)))
+ return -EFAULT;
+
+ set_out_fence_for_crtc(state->state, crtc, fence_ptr);
} else if (crtc->funcs->atomic_set_property)
return crtc->funcs->atomic_set_property(crtc, state, property, val);
else
@@ -533,6 +560,8 @@ drm_atomic_crtc_get_property(struct drm_crtc *crtc,
*val = (state->ctm) ? state->ctm->base.id : 0;
else if (property == config->gamma_lut_property)
*val = (state->gamma_lut) ? state->gamma_lut->base.id : 0;
+ else if (property == config->prop_out_fence_ptr)
+ *val = 0;
else if (crtc->funcs->atomic_get_property)
return crtc->funcs->atomic_get_property(crtc, state, property, val);
else
@@ -1659,11 +1688,9 @@ int drm_atomic_debugfs_init(struct drm_minor *minor)
*/
static struct drm_pending_vblank_event *create_vblank_event(
- struct drm_device *dev, struct drm_file *file_priv,
- struct dma_fence *fence, uint64_t user_data)
+ struct drm_device *dev, uint64_t user_data)
{
struct drm_pending_vblank_event *e = NULL;
- int ret;
e = kzalloc(sizeof *e, GFP_KERNEL);
if (!e)
@@ -1673,17 +1700,6 @@ static struct drm_pending_vblank_event *create_vblank_event(
e->event.base.length = sizeof(e->event);
e->event.user_data = user_data;
- if (file_priv) {
- ret = drm_event_reserve_init(dev, file_priv, &e->base,
- &e->event.base);
- if (ret) {
- kfree(e);
- return NULL;
- }
- }
-
- e->base.fence = fence;
-
return e;
}
@@ -1788,6 +1804,167 @@ void drm_atomic_clean_old_fb(struct drm_device *dev,
}
EXPORT_SYMBOL(drm_atomic_clean_old_fb);
+static struct dma_fence *get_crtc_fence(struct drm_crtc *crtc)
+{
+ struct dma_fence *fence;
+
+ fence = kzalloc(sizeof(*fence), GFP_KERNEL);
+ if (!fence)
+ return NULL;
+
+ dma_fence_init(fence, &drm_crtc_fence_ops, &crtc->fence_lock,
+ crtc->fence_context, ++crtc->fence_seqno);
+
+ return fence;
+}
+
+struct drm_out_fence_state {
+ s64 __user *out_fence_ptr;
+ struct sync_file *sync_file;
+ int fd;
+};
+
+static int setup_out_fence(struct drm_out_fence_state *fence_state,
+ struct dma_fence *fence)
+{
+ fence_state->fd = get_unused_fd_flags(O_CLOEXEC);
+ if (fence_state->fd < 0)
+ return fence_state->fd;
+
+ if (put_user(fence_state->fd, fence_state->out_fence_ptr))
+ return -EFAULT;
+
+ fence_state->sync_file = sync_file_create(fence);
+ if(!fence_state->sync_file)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static int prepare_crtc_signaling(struct drm_device *dev,
+ struct drm_atomic_state *state,
+ struct drm_mode_atomic *arg,
+ struct drm_file *file_priv,
+ struct drm_out_fence_state **fence_state,
+ unsigned int *num_fences)
+{
+ struct drm_crtc *crtc;
+ struct drm_crtc_state *crtc_state;
+ int i, ret;
+
+ for_each_crtc_in_state(state, crtc, crtc_state, i) {
+ u64 __user *fence_ptr;
+
+ fence_ptr = get_out_fence_for_crtc(crtc_state->state, crtc);
+
+ if (arg->flags & DRM_MODE_ATOMIC_TEST_ONLY && fence_ptr) {
+ if (put_user(-1, fence_ptr))
+ return -EFAULT;
+
+ continue;
+ }
+
+ if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT || fence_ptr) {
+ struct drm_pending_vblank_event *e;
+
+ e = create_vblank_event(dev, arg->user_data);
+ if (!e)
+ return -ENOMEM;
+
+ crtc_state->event = e;
+ }
+
+ if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
+ struct drm_pending_vblank_event *e = crtc_state->event;
+
+ if (!file_priv)
+ continue;
+
+ ret = drm_event_reserve_init(dev, file_priv, &e->base,
+ &e->event.base);
+ if (ret) {
+ kfree(e);
+ crtc_state->event = NULL;
+ return ret;
+ }
+ }
+
+ if (fence_ptr) {
+ struct dma_fence *fence;
+ struct drm_out_fence_state *f;
+
+ f = krealloc(*fence_state, sizeof(**fence_state) *
+ (*num_fences + 1), GFP_KERNEL);
+ if (!f)
+ return -ENOMEM;
+
+ f[*num_fences].out_fence_ptr = fence_ptr;
+ *fence_state = f;
+
+ fence = get_crtc_fence(crtc);
+ if (!fence) {
+ (*num_fences)++;
+ return -ENOMEM;
+ }
+
+ ret = setup_out_fence(&f[(*num_fences)++], fence);
+ if (ret) {
+ dma_fence_put(fence);
+ return ret;
+ }
+
+ crtc_state->event->base.fence = fence;
+
+ }
+ }
+
+ return 0;
+}
+
+static void complete_crtc_signaling(struct drm_device *dev,
+ struct drm_atomic_state *state,
+ struct drm_out_fence_state *fence_state,
+ unsigned int num_fences, int ret)
+{
+ struct drm_crtc *crtc;
+ struct drm_crtc_state *crtc_state;
+ int i;
+
+ if (!ret) {
+ for (i = 0; i < num_fences; i++)
+ fd_install(fence_state[i].fd,
+ fence_state[i].sync_file->file);
+ return;
+ }
+
+ for_each_crtc_in_state(state, crtc, crtc_state, i) {
+ /*
+ * TEST_ONLY and PAGE_FLIP_EVENT are mutually
+ * exclusive, if they weren't, this code should be
+ * called on success for TEST_ONLY too.
+ */
+ if (crtc_state->event)
+ drm_event_cancel_free(dev, &crtc_state->event->base);
+ }
+
+ if (!fence_state)
+ return;
+
+ for (i = 0; i < num_fences; i++) {
+ if (fence_state[i].sync_file)
+ fput(fence_state[i].sync_file->file);
+ if (fence_state[i].fd >= 0)
+ put_unused_fd(fence_state[i].fd);
+
+ /* If this fails log error to the user */
+ if (fence_state[i].out_fence_ptr &&
+ put_user(-1, fence_state[i].out_fence_ptr))
+ DRM_DEBUG_ATOMIC("Couldn't clear out_fence_ptr\n");
+ }
+
+ kfree(fence_state);
+}
+
int drm_mode_atomic_ioctl(struct drm_device *dev,
void *data, struct drm_file *file_priv)
{
@@ -1800,11 +1977,10 @@ int drm_mode_atomic_ioctl(struct drm_device *dev,
struct drm_atomic_state *state;
struct drm_modeset_acquire_ctx ctx;
struct drm_plane *plane;
- struct drm_crtc *crtc;
- struct drm_crtc_state *crtc_state;
+ struct drm_out_fence_state *fence_state = NULL;
unsigned plane_mask;
int ret = 0;
- unsigned int i, j;
+ unsigned int i, j, num_fences = 0;
/* disallow for drivers not supporting atomic: */
if (!drm_core_check_feature(dev, DRIVER_ATOMIC))
@@ -1919,20 +2095,10 @@ int drm_mode_atomic_ioctl(struct drm_device *dev,
drm_mode_object_unreference(obj);
}
- if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
- for_each_crtc_in_state(state, crtc, crtc_state, i) {
- struct drm_pending_vblank_event *e;
-
- e = create_vblank_event(dev, file_priv, NULL,
- arg->user_data);
- if (!e) {
- ret = -ENOMEM;
- goto out;
- }
-
- crtc_state->event = e;
- }
- }
+ ret = prepare_crtc_signaling(dev, state, arg, file_priv, &fence_state,
+ &num_fences);
+ if (ret)
+ goto out;
if (arg->flags & DRM_MODE_ATOMIC_TEST_ONLY) {
/*
@@ -1952,20 +2118,7 @@ int drm_mode_atomic_ioctl(struct drm_device *dev,
out:
drm_atomic_clean_old_fb(dev, plane_mask, ret);
- if (ret && arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
- /*
- * TEST_ONLY and PAGE_FLIP_EVENT are mutually exclusive,
- * if they weren't, this code should be called on success
- * for TEST_ONLY too.
- */
-
- for_each_crtc_in_state(state, crtc, crtc_state, i) {
- if (!crtc_state->event)
- continue;
-
- drm_event_cancel_free(dev, &crtc_state->event->base);
- }
- }
+ complete_crtc_signaling(dev, state, fence_state, num_fences, ret);
if (ret == -EDEADLK) {
drm_atomic_state_clear(state);
diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index 9b9881b..e8bc1ae 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -274,6 +274,8 @@ int drm_crtc_init_with_planes(struct drm_device *dev, struct drm_crtc *crtc,
if (drm_core_check_feature(dev, DRIVER_ATOMIC)) {
drm_object_attach_property(&crtc->base, config->prop_active, 0);
drm_object_attach_property(&crtc->base, config->prop_mode_id, 0);
+ drm_object_attach_property(&crtc->base,
+ config->prop_out_fence_ptr, 0);
}
return 0;
@@ -434,6 +436,12 @@ static int drm_mode_create_standard_properties(struct drm_device *dev)
return -ENOMEM;
dev->mode_config.prop_in_fence_fd = prop;
+ prop = drm_property_create_range(dev, DRM_MODE_PROP_ATOMIC,
+ "OUT_FENCE_PTR", 0, U64_MAX);
+ if (!prop)
+ return -ENOMEM;
+ dev->mode_config.prop_out_fence_ptr = prop;
+
prop = drm_property_create_object(dev, DRM_MODE_PROP_ATOMIC,
"CRTC_ID", DRM_MODE_OBJECT_CRTC);
if (!prop)
diff --git a/include/drm/drm_atomic.h b/include/drm/drm_atomic.h
index 331bb10..c0eaec7 100644
--- a/include/drm/drm_atomic.h
+++ b/include/drm/drm_atomic.h
@@ -144,6 +144,7 @@ struct __drm_crtcs_state {
struct drm_crtc *ptr;
struct drm_crtc_state *state;
struct drm_crtc_commit *commit;
+ s64 __user *out_fence_ptr;
};
struct __drm_connnectors_state {
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 0870de1..44571bc 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -1264,6 +1264,12 @@ struct drm_mode_config {
*/
struct drm_property *prop_in_fence_fd;
/**
+ * @prop_out_fence_ptr: Sync File fd pointer representing the
+ * outgoing fences for a CRTC. Userspace should provide a pointer to a
+ * value of type s64, and then cast that pointer to u64.
+ */
+ struct drm_property *prop_out_fence_ptr;
+ /**
* @prop_crtc_id: Default atomic plane property to specify the
* &drm_crtc.
*/
--
2.5.5
I tested this series on the db410c platform and I've seen no
regressions from previous versions of this series.
Tested-by: Robert Foss <[email protected]>
On Fri, Nov 11, 2016 at 9:15 AM, Gustavo Padovan <[email protected]> wrote:
> From: Gustavo Padovan <[email protected]>
>
> There is now a new property called IN_FENCE_FD attached to every plane
> state that receives sync_file fds from userspace via the atomic commit
> IOCTL.
>
> The fd is then translated to a fence (that may be a fence_array
> subclass or just a normal fence) and then used by DRM to fence_wait() for
> all fences in the sync_file to signal. So it only commits when all
> framebuffers are ready to scanout.
>
> v2: Comments by Daniel Vetter:
> - remove set state->fence = NULL in destroy phase
> - accept fence -1 as valid and just return 0
> - do not call fence_get() - sync_file_fences_get() already calls it
> - fence_put() if state->fence is already set, in case userspace
> set the property more than once.
>
> v3: WARN_ON if fence is set but state has no FB
>
> v4: Comment from Maarten Lankhorst
> - allow set fence with no related fb
>
> v5: rename FENCE_FD to IN_FENCE_FD
>
> v6: Comments by Daniel Vetter:
> - rename plane_state->in_fence back to "fence"
> - re-introduce WARN_ON if fence set but no fb
>
> - rebase after fence -> dma_fence rename
>
> v7: Comments by Brian Starkey
> - set state->fence to NULL when duplicating the state
> - fail if IN_FENCE_FD was already set
>
> Signed-off-by: Gustavo Padovan <[email protected]>
> Reviewed-by: Brian Starkey <[email protected]>
Reviewed-by: Sean Paul <[email protected]>
> ---
> drivers/gpu/drm/Kconfig | 1 +
> drivers/gpu/drm/drm_atomic.c | 14 ++++++++++++++
> drivers/gpu/drm/drm_atomic_helper.c | 5 +++++
> drivers/gpu/drm/drm_crtc.c | 6 ++++++
> drivers/gpu/drm/drm_plane.c | 1 +
> include/drm/drm_crtc.h | 5 +++++
> 6 files changed, 32 insertions(+)
>
> diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
> index 25e8e37..360cb92 100644
> --- a/drivers/gpu/drm/Kconfig
> +++ b/drivers/gpu/drm/Kconfig
> @@ -12,6 +12,7 @@ menuconfig DRM
> select I2C
> select I2C_ALGOBIT
> select DMA_SHARED_BUFFER
> + select SYNC_FILE
> help
> Kernel-level support for the Direct Rendering Infrastructure (DRI)
> introduced in XFree86 4.0. If you say Y here, you need to select
> diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
> index b096c16..8e26ad1 100644
> --- a/drivers/gpu/drm/drm_atomic.c
> +++ b/drivers/gpu/drm/drm_atomic.c
> @@ -31,6 +31,7 @@
> #include <drm/drm_mode.h>
> #include <drm/drm_plane_helper.h>
> #include <drm/drm_print.h>
> +#include <linux/sync_file.h>
>
> #include "drm_crtc_internal.h"
>
> @@ -709,6 +710,17 @@ int drm_atomic_plane_set_property(struct drm_plane *plane,
> drm_atomic_set_fb_for_plane(state, fb);
> if (fb)
> drm_framebuffer_unreference(fb);
> + } else if (property == config->prop_in_fence_fd) {
> + if (state->fence)
> + return -EINVAL;
> +
> + if (U642I64(val) == -1)
> + return 0;
> +
> + state->fence = sync_file_get_fence(val);
> + if (!state->fence)
> + return -EINVAL;
> +
> } else if (property == config->prop_crtc_id) {
> struct drm_crtc *crtc = drm_crtc_find(dev, val);
> return drm_atomic_set_crtc_for_plane(state, crtc);
> @@ -770,6 +782,8 @@ drm_atomic_plane_get_property(struct drm_plane *plane,
>
> if (property == config->prop_fb_id) {
> *val = (state->fb) ? state->fb->base.id : 0;
> + } else if (property == config->prop_in_fence_fd) {
> + *val = -1;
> } else if (property == config->prop_crtc_id) {
> *val = (state->crtc) ? state->crtc->base.id : 0;
> } else if (property == config->prop_crtc_x) {
> diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
> index 75ad01d..caed870 100644
> --- a/drivers/gpu/drm/drm_atomic_helper.c
> +++ b/drivers/gpu/drm/drm_atomic_helper.c
> @@ -3076,6 +3076,8 @@ void __drm_atomic_helper_plane_duplicate_state(struct drm_plane *plane,
>
> if (state->fb)
> drm_framebuffer_reference(state->fb);
> +
> + state->fence = NULL;
> }
> EXPORT_SYMBOL(__drm_atomic_helper_plane_duplicate_state);
>
> @@ -3114,6 +3116,9 @@ void __drm_atomic_helper_plane_destroy_state(struct drm_plane_state *state)
> {
> if (state->fb)
> drm_framebuffer_unreference(state->fb);
> +
> + if (state->fence)
> + dma_fence_put(state->fence);
> }
> EXPORT_SYMBOL(__drm_atomic_helper_plane_destroy_state);
>
> diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
> index ce274ed..154e040 100644
> --- a/drivers/gpu/drm/drm_crtc.c
> +++ b/drivers/gpu/drm/drm_crtc.c
> @@ -397,6 +397,12 @@ static int drm_mode_create_standard_properties(struct drm_device *dev)
> return -ENOMEM;
> dev->mode_config.prop_fb_id = prop;
>
> + prop = drm_property_create_signed_range(dev, DRM_MODE_PROP_ATOMIC,
> + "IN_FENCE_FD", -1, INT_MAX);
> + if (!prop)
> + return -ENOMEM;
> + dev->mode_config.prop_in_fence_fd = prop;
> +
> prop = drm_property_create_object(dev, DRM_MODE_PROP_ATOMIC,
> "CRTC_ID", DRM_MODE_OBJECT_CRTC);
> if (!prop)
> diff --git a/drivers/gpu/drm/drm_plane.c b/drivers/gpu/drm/drm_plane.c
> index 249c0ae..3957ef8 100644
> --- a/drivers/gpu/drm/drm_plane.c
> +++ b/drivers/gpu/drm/drm_plane.c
> @@ -137,6 +137,7 @@ int drm_universal_plane_init(struct drm_device *dev, struct drm_plane *plane,
>
> if (drm_core_check_feature(dev, DRIVER_ATOMIC)) {
> drm_object_attach_property(&plane->base, config->prop_fb_id, 0);
> + drm_object_attach_property(&plane->base, config->prop_in_fence_fd, -1);
> drm_object_attach_property(&plane->base, config->prop_crtc_id, 0);
> drm_object_attach_property(&plane->base, config->prop_crtc_x, 0);
> drm_object_attach_property(&plane->base, config->prop_crtc_y, 0);
> diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
> index 8cca2a8..11780a9 100644
> --- a/include/drm/drm_crtc.h
> +++ b/include/drm/drm_crtc.h
> @@ -1214,6 +1214,11 @@ struct drm_mode_config {
> */
> struct drm_property *prop_fb_id;
> /**
> + * @prop_in_fence_fd: Sync File fd representing the incoming fences
> + * for a Plane.
> + */
> + struct drm_property *prop_in_fence_fd;
> + /**
> * @prop_crtc_id: Default atomic plane property to specify the
> * &drm_crtc.
> */
> --
> 2.5.5
>
On Fri, Nov 11, 2016 at 9:15 AM, Gustavo Padovan <[email protected]> wrote:
> From: Gustavo Padovan <[email protected]>
>
> Support DRM out-fences by creating a sync_file with a fence for each CRTC
> that sets the OUT_FENCE_PTR property.
>
> We use the out_fence pointer received in the OUT_FENCE_PTR prop to send
> the sync_file fd back to userspace.
>
> The sync_file and fd are allocated/created before commit, but the
> fd_install operation only happens after we know that commit succeed.
>
> v2: Comment by Rob Clark:
> - Squash commit that adds DRM_MODE_ATOMIC_OUT_FENCE flag here.
>
> Comment by Daniel Vetter:
> - Add clean up code for out_fences
>
> v3: Comments by Daniel Vetter:
> - create DRM_MODE_ATOMIC_EVENT_MASK
> - userspace should fill out_fences_ptr with the crtc_ids for which
> it wants fences back.
>
> v4: Create OUT_FENCE_PTR properties and remove old approach.
>
> v5: Comments by Brian Starkey:
> - Remove extra fence_get() in atomic_ioctl()
> - Check ret before iterating on the crtc_state
> - check ret before fd_install
> - set fence_state to NULL at the beginning
> - check fence_state->out_fence_ptr before put_user()
> - change order of fput() and put_unused_fd() on failure
>
> - Add access_ok() check to the out_fence_ptr received
> - Rebase after fence -> dma_fence rename
> - Store out_fence_ptr in the drm_atomic_state
> - Split crtc_setup_out_fence()
> - return -1 as out_fence with TEST_ONLY flag
>
> v6: Comments by Daniel Vetter
> - Add prepare/unprepare_crtc_signaling()
> - move struct drm_out_fence_state to drm_atomic.c
> - mark get_crtc_fence() as static
>
> Comments by Brian Starkey
> - proper set fence_ptr fence_state array
> - isolate fence_idx increment
>
> - improve error handling
>
> v7: Comments by Daniel Vetter
> - remove prefix from internal functions
> - make out_fence_ptr an s64 pointer
> - degrade DRM_INFO to DRM_DEBUG_ATOMIC when put_user fail
> - fix doc issues
> - filter out OUT_FENCE_PTR == NULL and do not fail in this case
> - add complete_crtc_signalling()
> - krealloc fence_state on demand
>
> Comment by Brian Starkey
> - remove unused crtc_state arg from get_out_fence()
>
> v8: Comment by Brian Starkey
> - cancel events before check for !fence_state
> - convert a few lefovers u64 types for out_fence_ptr
> - fix memleak by assign fence_state earlier after realloc
> - proper accout num_fences in case of error
>
> Signed-off-by: Gustavo Padovan <[email protected]>
A couple of nits below, other than that, looks good to me
> ---
> drivers/gpu/drm/drm_atomic.c | 243 +++++++++++++++++++++++++++++++++++--------
> drivers/gpu/drm/drm_crtc.c | 8 ++
> include/drm/drm_atomic.h | 1 +
> include/drm/drm_crtc.h | 6 ++
> 4 files changed, 213 insertions(+), 45 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
> index 8e26ad1..34cdc6e 100644
> --- a/drivers/gpu/drm/drm_atomic.c
> +++ b/drivers/gpu/drm/drm_atomic.c
> @@ -290,6 +290,23 @@ drm_atomic_get_crtc_state(struct drm_atomic_state *state,
> }
> EXPORT_SYMBOL(drm_atomic_get_crtc_state);
>
> +static void set_out_fence_for_crtc(struct drm_atomic_state *state,
> + struct drm_crtc *crtc, s64 __user *fence_ptr)
> +{
> + state->crtcs[drm_crtc_index(crtc)].out_fence_ptr = fence_ptr;
> +}
> +
> +static s64 __user * get_out_fence_for_crtc(struct drm_atomic_state *state,
> + struct drm_crtc *crtc)
> +{
> + s64 __user *fence_ptr;
> +
> + fence_ptr = state->crtcs[drm_crtc_index(crtc)].out_fence_ptr;
> + state->crtcs[drm_crtc_index(crtc)].out_fence_ptr = NULL;
> +
> + return fence_ptr;
> +}
> +
> /**
> * drm_atomic_set_mode_for_crtc - set mode for CRTC
> * @state: the CRTC whose incoming state to update
> @@ -491,6 +508,16 @@ int drm_atomic_crtc_set_property(struct drm_crtc *crtc,
> &replaced);
> state->color_mgmt_changed |= replaced;
> return ret;
> + } else if (property == config->prop_out_fence_ptr) {
> + s64 __user *fence_ptr = u64_to_user_ptr(val);
> +
> + if (!fence_ptr)
> + return 0;
> +
> + if (!access_ok(VERIFY_WRITE, fence_ptr, sizeof(*fence_ptr)))
> + return -EFAULT;
> +
> + set_out_fence_for_crtc(state->state, crtc, fence_ptr);
> } else if (crtc->funcs->atomic_set_property)
> return crtc->funcs->atomic_set_property(crtc, state, property, val);
> else
> @@ -533,6 +560,8 @@ drm_atomic_crtc_get_property(struct drm_crtc *crtc,
> *val = (state->ctm) ? state->ctm->base.id : 0;
> else if (property == config->gamma_lut_property)
> *val = (state->gamma_lut) ? state->gamma_lut->base.id : 0;
> + else if (property == config->prop_out_fence_ptr)
> + *val = 0;
> else if (crtc->funcs->atomic_get_property)
> return crtc->funcs->atomic_get_property(crtc, state, property, val);
> else
> @@ -1659,11 +1688,9 @@ int drm_atomic_debugfs_init(struct drm_minor *minor)
> */
>
> static struct drm_pending_vblank_event *create_vblank_event(
> - struct drm_device *dev, struct drm_file *file_priv,
> - struct dma_fence *fence, uint64_t user_data)
> + struct drm_device *dev, uint64_t user_data)
> {
> struct drm_pending_vblank_event *e = NULL;
> - int ret;
>
> e = kzalloc(sizeof *e, GFP_KERNEL);
> if (!e)
> @@ -1673,17 +1700,6 @@ static struct drm_pending_vblank_event *create_vblank_event(
> e->event.base.length = sizeof(e->event);
> e->event.user_data = user_data;
>
> - if (file_priv) {
> - ret = drm_event_reserve_init(dev, file_priv, &e->base,
> - &e->event.base);
> - if (ret) {
> - kfree(e);
> - return NULL;
> - }
> - }
> -
> - e->base.fence = fence;
> -
> return e;
> }
>
> @@ -1788,6 +1804,167 @@ void drm_atomic_clean_old_fb(struct drm_device *dev,
> }
> EXPORT_SYMBOL(drm_atomic_clean_old_fb);
>
> +static struct dma_fence *get_crtc_fence(struct drm_crtc *crtc)
> +{
> + struct dma_fence *fence;
> +
> + fence = kzalloc(sizeof(*fence), GFP_KERNEL);
> + if (!fence)
> + return NULL;
> +
> + dma_fence_init(fence, &drm_crtc_fence_ops, &crtc->fence_lock,
> + crtc->fence_context, ++crtc->fence_seqno);
> +
> + return fence;
> +}
> +
> +struct drm_out_fence_state {
> + s64 __user *out_fence_ptr;
> + struct sync_file *sync_file;
> + int fd;
> +};
> +
> +static int setup_out_fence(struct drm_out_fence_state *fence_state,
> + struct dma_fence *fence)
> +{
> + fence_state->fd = get_unused_fd_flags(O_CLOEXEC);
> + if (fence_state->fd < 0)
> + return fence_state->fd;
> +
> + if (put_user(fence_state->fd, fence_state->out_fence_ptr))
> + return -EFAULT;
> +
> + fence_state->sync_file = sync_file_create(fence);
> + if(!fence_state->sync_file)
> + return -ENOMEM;
> +
> + return 0;
> +}
> +
> +static int prepare_crtc_signaling(struct drm_device *dev,
> + struct drm_atomic_state *state,
> + struct drm_mode_atomic *arg,
> + struct drm_file *file_priv,
> + struct drm_out_fence_state **fence_state,
> + unsigned int *num_fences)
> +{
> + struct drm_crtc *crtc;
> + struct drm_crtc_state *crtc_state;
> + int i, ret;
> +
> + for_each_crtc_in_state(state, crtc, crtc_state, i) {
> + u64 __user *fence_ptr;
> +
> + fence_ptr = get_out_fence_for_crtc(crtc_state->state, crtc);
> +
> + if (arg->flags & DRM_MODE_ATOMIC_TEST_ONLY && fence_ptr) {
> + if (put_user(-1, fence_ptr))
> + return -EFAULT;
> +
> + continue;
> + }
> +
> + if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT || fence_ptr) {
pedantic suggestion: If you did the inverse, you could just continue
and save yourself some indentation (and instantiate e once). ie:
if (!(arg->flags & DRM_MODE_PAGE_FLIP_EVENT) && !fence_ptr)
continue;
...
> + struct drm_pending_vblank_event *e;
> +
> + e = create_vblank_event(dev, arg->user_data);
> + if (!e)
> + return -ENOMEM;
> +
> + crtc_state->event = e;
> + }
> +
> + if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
> + struct drm_pending_vblank_event *e = crtc_state->event;
> +
> + if (!file_priv)
> + continue;
> +
> + ret = drm_event_reserve_init(dev, file_priv, &e->base,
> + &e->event.base);
> + if (ret) {
> + kfree(e);
> + crtc_state->event = NULL;
> + return ret;
> + }
> + }
> +
> + if (fence_ptr) {
> + struct dma_fence *fence;
> + struct drm_out_fence_state *f;
> +
> + f = krealloc(*fence_state, sizeof(**fence_state) *
> + (*num_fences + 1), GFP_KERNEL);
> + if (!f)
> + return -ENOMEM;
> +
> + f[*num_fences].out_fence_ptr = fence_ptr;
> + *fence_state = f;
> +
> + fence = get_crtc_fence(crtc);
> + if (!fence) {
> + (*num_fences)++;
> + return -ENOMEM;
> + }
> +
> + ret = setup_out_fence(&f[(*num_fences)++], fence);
> + if (ret) {
> + dma_fence_put(fence);
> + return ret;
> + }
> +
> + crtc_state->event->base.fence = fence;
> +
> + }
> + }
> +
> + return 0;
> +}
> +
> +static void complete_crtc_signaling(struct drm_device *dev,
> + struct drm_atomic_state *state,
> + struct drm_out_fence_state *fence_state,
> + unsigned int num_fences, int ret)
> +{
> + struct drm_crtc *crtc;
> + struct drm_crtc_state *crtc_state;
> + int i;
> +
> + if (!ret) {
I don't think there's any reason to smash the fd install and clean-up
into one function. I think splitting into 2 functions and calling the
right one from atomic_ioctl would be better.
> + for (i = 0; i < num_fences; i++)
> + fd_install(fence_state[i].fd,
> + fence_state[i].sync_file->file);
> + return;
> + }
> +
> + for_each_crtc_in_state(state, crtc, crtc_state, i) {
> + /*
> + * TEST_ONLY and PAGE_FLIP_EVENT are mutually
> + * exclusive, if they weren't, this code should be
> + * called on success for TEST_ONLY too.
> + */
> + if (crtc_state->event)
> + drm_event_cancel_free(dev, &crtc_state->event->base);
> + }
> +
> + if (!fence_state)
> + return;
> +
> + for (i = 0; i < num_fences; i++) {
> + if (fence_state[i].sync_file)
> + fput(fence_state[i].sync_file->file);
> + if (fence_state[i].fd >= 0)
> + put_unused_fd(fence_state[i].fd);
> +
> + /* If this fails log error to the user */
> + if (fence_state[i].out_fence_ptr &&
> + put_user(-1, fence_state[i].out_fence_ptr))
> + DRM_DEBUG_ATOMIC("Couldn't clear out_fence_ptr\n");
> + }
> +
> + kfree(fence_state);
> +}
> +
> int drm_mode_atomic_ioctl(struct drm_device *dev,
> void *data, struct drm_file *file_priv)
> {
> @@ -1800,11 +1977,10 @@ int drm_mode_atomic_ioctl(struct drm_device *dev,
> struct drm_atomic_state *state;
> struct drm_modeset_acquire_ctx ctx;
> struct drm_plane *plane;
> - struct drm_crtc *crtc;
> - struct drm_crtc_state *crtc_state;
> + struct drm_out_fence_state *fence_state = NULL;
> unsigned plane_mask;
> int ret = 0;
> - unsigned int i, j;
> + unsigned int i, j, num_fences = 0;
>
> /* disallow for drivers not supporting atomic: */
> if (!drm_core_check_feature(dev, DRIVER_ATOMIC))
> @@ -1919,20 +2095,10 @@ int drm_mode_atomic_ioctl(struct drm_device *dev,
> drm_mode_object_unreference(obj);
> }
>
> - if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
> - for_each_crtc_in_state(state, crtc, crtc_state, i) {
> - struct drm_pending_vblank_event *e;
> -
> - e = create_vblank_event(dev, file_priv, NULL,
> - arg->user_data);
> - if (!e) {
> - ret = -ENOMEM;
> - goto out;
> - }
> -
> - crtc_state->event = e;
> - }
> - }
> + ret = prepare_crtc_signaling(dev, state, arg, file_priv, &fence_state,
> + &num_fences);
> + if (ret)
> + goto out;
>
> if (arg->flags & DRM_MODE_ATOMIC_TEST_ONLY) {
> /*
> @@ -1952,20 +2118,7 @@ int drm_mode_atomic_ioctl(struct drm_device *dev,
> out:
> drm_atomic_clean_old_fb(dev, plane_mask, ret);
>
> - if (ret && arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
> - /*
> - * TEST_ONLY and PAGE_FLIP_EVENT are mutually exclusive,
> - * if they weren't, this code should be called on success
> - * for TEST_ONLY too.
> - */
> -
> - for_each_crtc_in_state(state, crtc, crtc_state, i) {
> - if (!crtc_state->event)
> - continue;
> -
> - drm_event_cancel_free(dev, &crtc_state->event->base);
> - }
> - }
> + complete_crtc_signaling(dev, state, fence_state, num_fences, ret);
>
> if (ret == -EDEADLK) {
> drm_atomic_state_clear(state);
> diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
> index 9b9881b..e8bc1ae 100644
> --- a/drivers/gpu/drm/drm_crtc.c
> +++ b/drivers/gpu/drm/drm_crtc.c
> @@ -274,6 +274,8 @@ int drm_crtc_init_with_planes(struct drm_device *dev, struct drm_crtc *crtc,
> if (drm_core_check_feature(dev, DRIVER_ATOMIC)) {
> drm_object_attach_property(&crtc->base, config->prop_active, 0);
> drm_object_attach_property(&crtc->base, config->prop_mode_id, 0);
> + drm_object_attach_property(&crtc->base,
> + config->prop_out_fence_ptr, 0);
> }
>
> return 0;
> @@ -434,6 +436,12 @@ static int drm_mode_create_standard_properties(struct drm_device *dev)
> return -ENOMEM;
> dev->mode_config.prop_in_fence_fd = prop;
>
> + prop = drm_property_create_range(dev, DRM_MODE_PROP_ATOMIC,
> + "OUT_FENCE_PTR", 0, U64_MAX);
> + if (!prop)
> + return -ENOMEM;
> + dev->mode_config.prop_out_fence_ptr = prop;
> +
> prop = drm_property_create_object(dev, DRM_MODE_PROP_ATOMIC,
> "CRTC_ID", DRM_MODE_OBJECT_CRTC);
> if (!prop)
> diff --git a/include/drm/drm_atomic.h b/include/drm/drm_atomic.h
> index 331bb10..c0eaec7 100644
> --- a/include/drm/drm_atomic.h
> +++ b/include/drm/drm_atomic.h
> @@ -144,6 +144,7 @@ struct __drm_crtcs_state {
> struct drm_crtc *ptr;
> struct drm_crtc_state *state;
> struct drm_crtc_commit *commit;
> + s64 __user *out_fence_ptr;
> };
>
> struct __drm_connnectors_state {
> diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
> index 0870de1..44571bc 100644
> --- a/include/drm/drm_crtc.h
> +++ b/include/drm/drm_crtc.h
> @@ -1264,6 +1264,12 @@ struct drm_mode_config {
> */
> struct drm_property *prop_in_fence_fd;
> /**
> + * @prop_out_fence_ptr: Sync File fd pointer representing the
> + * outgoing fences for a CRTC. Userspace should provide a pointer to a
> + * value of type s64, and then cast that pointer to u64.
> + */
> + struct drm_property *prop_out_fence_ptr;
> + /**
> * @prop_crtc_id: Default atomic plane property to specify the
> * &drm_crtc.
> */
> --
> 2.5.5
>
On Fri, Nov 11, 2016 at 11:48:09AM -0500, Sean Paul wrote:
> On Fri, Nov 11, 2016 at 9:15 AM, Gustavo Padovan <[email protected]> wrote:
> > +static void complete_crtc_signaling(struct drm_device *dev,
> > + struct drm_atomic_state *state,
> > + struct drm_out_fence_state *fence_state,
> > + unsigned int num_fences, int ret)
> > +{
> > + struct drm_crtc *crtc;
> > + struct drm_crtc_state *crtc_state;
> > + int i;
> > +
> > + if (!ret) {
>
> I don't think there's any reason to smash the fd install and clean-up
> into one function. I think splitting into 2 functions and calling the
> right one from atomic_ioctl would be better.
Hm, I suggested this because the control flow in one of Gustavo's earlier
patches look really funny. I guess it could be split up again, but with
both callers in the current position. tbh I don't care whether it's this
or that, both are clear improvement over the older version.
-Daniel
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
On Fri, Nov 11, 2016 at 12:11 PM, Daniel Vetter <[email protected]> wrote:
> On Fri, Nov 11, 2016 at 11:48:09AM -0500, Sean Paul wrote:
>> On Fri, Nov 11, 2016 at 9:15 AM, Gustavo Padovan <[email protected]> wrote:
>> > +static void complete_crtc_signaling(struct drm_device *dev,
>> > + struct drm_atomic_state *state,
>> > + struct drm_out_fence_state *fence_state,
>> > + unsigned int num_fences, int ret)
>> > +{
>> > + struct drm_crtc *crtc;
>> > + struct drm_crtc_state *crtc_state;
>> > + int i;
>> > +
>> > + if (!ret) {
>>
>> I don't think there's any reason to smash the fd install and clean-up
>> into one function. I think splitting into 2 functions and calling the
>> right one from atomic_ioctl would be better.
>
> Hm, I suggested this because the control flow in one of Gustavo's earlier
> patches look really funny. I guess it could be split up again, but with
> both callers in the current position. tbh I don't care whether it's this
> or that, both are clear improvement over the older version.
I really don't have a strong opinion either. Perhaps meet in the
middle and pass bool install_fds instead of ret (since that's kind of
an anti-pattern)?
Sean
> -Daniel
> --
> Daniel Vetter
> Software Engineer, Intel Corporation
> http://blog.ffwll.ch
Spotted one more thing on a cleanup path...
On Fri, Nov 11, 2016 at 11:15:59PM +0900, Gustavo Padovan wrote:
>From: Gustavo Padovan <[email protected]>
>
>Support DRM out-fences by creating a sync_file with a fence for each CRTC
>that sets the OUT_FENCE_PTR property.
>
>We use the out_fence pointer received in the OUT_FENCE_PTR prop to send
>the sync_file fd back to userspace.
>
>The sync_file and fd are allocated/created before commit, but the
>fd_install operation only happens after we know that commit succeed.
>
>v2: Comment by Rob Clark:
> - Squash commit that adds DRM_MODE_ATOMIC_OUT_FENCE flag here.
>
> Comment by Daniel Vetter:
> - Add clean up code for out_fences
>
>v3: Comments by Daniel Vetter:
> - create DRM_MODE_ATOMIC_EVENT_MASK
> - userspace should fill out_fences_ptr with the crtc_ids for which
> it wants fences back.
>
>v4: Create OUT_FENCE_PTR properties and remove old approach.
>
>v5: Comments by Brian Starkey:
> - Remove extra fence_get() in atomic_ioctl()
> - Check ret before iterating on the crtc_state
> - check ret before fd_install
> - set fence_state to NULL at the beginning
> - check fence_state->out_fence_ptr before put_user()
> - change order of fput() and put_unused_fd() on failure
>
> - Add access_ok() check to the out_fence_ptr received
> - Rebase after fence -> dma_fence rename
> - Store out_fence_ptr in the drm_atomic_state
> - Split crtc_setup_out_fence()
> - return -1 as out_fence with TEST_ONLY flag
>
>v6: Comments by Daniel Vetter
> - Add prepare/unprepare_crtc_signaling()
> - move struct drm_out_fence_state to drm_atomic.c
> - mark get_crtc_fence() as static
>
> Comments by Brian Starkey
> - proper set fence_ptr fence_state array
> - isolate fence_idx increment
>
> - improve error handling
>
>v7: Comments by Daniel Vetter
> - remove prefix from internal functions
> - make out_fence_ptr an s64 pointer
> - degrade DRM_INFO to DRM_DEBUG_ATOMIC when put_user fail
> - fix doc issues
> - filter out OUT_FENCE_PTR == NULL and do not fail in this case
> - add complete_crtc_signalling()
> - krealloc fence_state on demand
>
> Comment by Brian Starkey
> - remove unused crtc_state arg from get_out_fence()
>
>v8: Comment by Brian Starkey
> - cancel events before check for !fence_state
> - convert a few lefovers u64 types for out_fence_ptr
> - fix memleak by assign fence_state earlier after realloc
> - proper accout num_fences in case of error
>
>Signed-off-by: Gustavo Padovan <[email protected]>
>---
> drivers/gpu/drm/drm_atomic.c | 243 +++++++++++++++++++++++++++++++++++--------
> drivers/gpu/drm/drm_crtc.c | 8 ++
> include/drm/drm_atomic.h | 1 +
> include/drm/drm_crtc.h | 6 ++
> 4 files changed, 213 insertions(+), 45 deletions(-)
>
>diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
>index 8e26ad1..34cdc6e 100644
>--- a/drivers/gpu/drm/drm_atomic.c
>+++ b/drivers/gpu/drm/drm_atomic.c
>@@ -290,6 +290,23 @@ drm_atomic_get_crtc_state(struct drm_atomic_state *state,
> }
> EXPORT_SYMBOL(drm_atomic_get_crtc_state);
>
>+static void set_out_fence_for_crtc(struct drm_atomic_state *state,
>+ struct drm_crtc *crtc, s64 __user *fence_ptr)
>+{
>+ state->crtcs[drm_crtc_index(crtc)].out_fence_ptr = fence_ptr;
>+}
>+
>+static s64 __user * get_out_fence_for_crtc(struct drm_atomic_state *state,
>+ struct drm_crtc *crtc)
>+{
>+ s64 __user *fence_ptr;
>+
>+ fence_ptr = state->crtcs[drm_crtc_index(crtc)].out_fence_ptr;
>+ state->crtcs[drm_crtc_index(crtc)].out_fence_ptr = NULL;
>+
>+ return fence_ptr;
>+}
>+
> /**
> * drm_atomic_set_mode_for_crtc - set mode for CRTC
> * @state: the CRTC whose incoming state to update
>@@ -491,6 +508,16 @@ int drm_atomic_crtc_set_property(struct drm_crtc *crtc,
> &replaced);
> state->color_mgmt_changed |= replaced;
> return ret;
>+ } else if (property == config->prop_out_fence_ptr) {
>+ s64 __user *fence_ptr = u64_to_user_ptr(val);
>+
>+ if (!fence_ptr)
>+ return 0;
>+
>+ if (!access_ok(VERIFY_WRITE, fence_ptr, sizeof(*fence_ptr)))
>+ return -EFAULT;
>+
>+ set_out_fence_for_crtc(state->state, crtc, fence_ptr);
> } else if (crtc->funcs->atomic_set_property)
> return crtc->funcs->atomic_set_property(crtc, state, property, val);
> else
>@@ -533,6 +560,8 @@ drm_atomic_crtc_get_property(struct drm_crtc *crtc,
> *val = (state->ctm) ? state->ctm->base.id : 0;
> else if (property == config->gamma_lut_property)
> *val = (state->gamma_lut) ? state->gamma_lut->base.id : 0;
>+ else if (property == config->prop_out_fence_ptr)
>+ *val = 0;
> else if (crtc->funcs->atomic_get_property)
> return crtc->funcs->atomic_get_property(crtc, state, property, val);
> else
>@@ -1659,11 +1688,9 @@ int drm_atomic_debugfs_init(struct drm_minor *minor)
> */
>
> static struct drm_pending_vblank_event *create_vblank_event(
>- struct drm_device *dev, struct drm_file *file_priv,
>- struct dma_fence *fence, uint64_t user_data)
>+ struct drm_device *dev, uint64_t user_data)
> {
> struct drm_pending_vblank_event *e = NULL;
>- int ret;
>
> e = kzalloc(sizeof *e, GFP_KERNEL);
> if (!e)
>@@ -1673,17 +1700,6 @@ static struct drm_pending_vblank_event *create_vblank_event(
> e->event.base.length = sizeof(e->event);
> e->event.user_data = user_data;
>
>- if (file_priv) {
>- ret = drm_event_reserve_init(dev, file_priv, &e->base,
>- &e->event.base);
>- if (ret) {
>- kfree(e);
>- return NULL;
>- }
>- }
>-
>- e->base.fence = fence;
>-
> return e;
> }
>
>@@ -1788,6 +1804,167 @@ void drm_atomic_clean_old_fb(struct drm_device *dev,
> }
> EXPORT_SYMBOL(drm_atomic_clean_old_fb);
>
>+static struct dma_fence *get_crtc_fence(struct drm_crtc *crtc)
>+{
>+ struct dma_fence *fence;
>+
>+ fence = kzalloc(sizeof(*fence), GFP_KERNEL);
>+ if (!fence)
>+ return NULL;
>+
>+ dma_fence_init(fence, &drm_crtc_fence_ops, &crtc->fence_lock,
>+ crtc->fence_context, ++crtc->fence_seqno);
>+
>+ return fence;
>+}
>+
>+struct drm_out_fence_state {
>+ s64 __user *out_fence_ptr;
>+ struct sync_file *sync_file;
>+ int fd;
>+};
>+
>+static int setup_out_fence(struct drm_out_fence_state *fence_state,
>+ struct dma_fence *fence)
>+{
>+ fence_state->fd = get_unused_fd_flags(O_CLOEXEC);
>+ if (fence_state->fd < 0)
>+ return fence_state->fd;
>+
>+ if (put_user(fence_state->fd, fence_state->out_fence_ptr))
>+ return -EFAULT;
>+
>+ fence_state->sync_file = sync_file_create(fence);
>+ if(!fence_state->sync_file)
>+ return -ENOMEM;
>+
>+ return 0;
>+}
>+
>+static int prepare_crtc_signaling(struct drm_device *dev,
>+ struct drm_atomic_state *state,
>+ struct drm_mode_atomic *arg,
>+ struct drm_file *file_priv,
>+ struct drm_out_fence_state **fence_state,
>+ unsigned int *num_fences)
>+{
>+ struct drm_crtc *crtc;
>+ struct drm_crtc_state *crtc_state;
>+ int i, ret;
>+
>+ for_each_crtc_in_state(state, crtc, crtc_state, i) {
>+ u64 __user *fence_ptr;
>+
>+ fence_ptr = get_out_fence_for_crtc(crtc_state->state, crtc);
>+
>+ if (arg->flags & DRM_MODE_ATOMIC_TEST_ONLY && fence_ptr) {
>+ if (put_user(-1, fence_ptr))
>+ return -EFAULT;
>+
>+ continue;
>+ }
>+
>+ if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT || fence_ptr) {
>+ struct drm_pending_vblank_event *e;
>+
>+ e = create_vblank_event(dev, arg->user_data);
>+ if (!e)
>+ return -ENOMEM;
>+
>+ crtc_state->event = e;
>+ }
>+
>+ if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
>+ struct drm_pending_vblank_event *e = crtc_state->event;
>+
>+ if (!file_priv)
>+ continue;
>+
>+ ret = drm_event_reserve_init(dev, file_priv, &e->base,
>+ &e->event.base);
>+ if (ret) {
>+ kfree(e);
>+ crtc_state->event = NULL;
>+ return ret;
>+ }
>+ }
>+
>+ if (fence_ptr) {
>+ struct dma_fence *fence;
>+ struct drm_out_fence_state *f;
>+
>+ f = krealloc(*fence_state, sizeof(**fence_state) *
>+ (*num_fences + 1), GFP_KERNEL);
>+ if (!f)
>+ return -ENOMEM;
We have to make sure the new bit of fence_state is zeroed, otherwise
failing after the (*num_fences)++ could lead to fput/put_unused_fd on
random numbers.
-Brian
>+
>+ f[*num_fences].out_fence_ptr = fence_ptr;
>+ *fence_state = f;
>+
>+ fence = get_crtc_fence(crtc);
>+ if (!fence) {
>+ (*num_fences)++;
>+ return -ENOMEM;
>+ }
>+
>+ ret = setup_out_fence(&f[(*num_fences)++], fence);
>+ if (ret) {
>+ dma_fence_put(fence);
>+ return ret;
>+ }
>+
>+ crtc_state->event->base.fence = fence;
>+
>+ }
>+ }
>+
>+ return 0;
>+}
>+
>+static void complete_crtc_signaling(struct drm_device *dev,
>+ struct drm_atomic_state *state,
>+ struct drm_out_fence_state *fence_state,
>+ unsigned int num_fences, int ret)
>+{
>+ struct drm_crtc *crtc;
>+ struct drm_crtc_state *crtc_state;
>+ int i;
>+
>+ if (!ret) {
>+ for (i = 0; i < num_fences; i++)
>+ fd_install(fence_state[i].fd,
>+ fence_state[i].sync_file->file);
>+ return;
>+ }
>+
>+ for_each_crtc_in_state(state, crtc, crtc_state, i) {
>+ /*
>+ * TEST_ONLY and PAGE_FLIP_EVENT are mutually
>+ * exclusive, if they weren't, this code should be
>+ * called on success for TEST_ONLY too.
>+ */
>+ if (crtc_state->event)
>+ drm_event_cancel_free(dev, &crtc_state->event->base);
>+ }
>+
>+ if (!fence_state)
>+ return;
>+
>+ for (i = 0; i < num_fences; i++) {
>+ if (fence_state[i].sync_file)
>+ fput(fence_state[i].sync_file->file);
>+ if (fence_state[i].fd >= 0)
>+ put_unused_fd(fence_state[i].fd);
>+
>+ /* If this fails log error to the user */
>+ if (fence_state[i].out_fence_ptr &&
>+ put_user(-1, fence_state[i].out_fence_ptr))
>+ DRM_DEBUG_ATOMIC("Couldn't clear out_fence_ptr\n");
>+ }
>+
>+ kfree(fence_state);
>+}
>+
> int drm_mode_atomic_ioctl(struct drm_device *dev,
> void *data, struct drm_file *file_priv)
> {
>@@ -1800,11 +1977,10 @@ int drm_mode_atomic_ioctl(struct drm_device *dev,
> struct drm_atomic_state *state;
> struct drm_modeset_acquire_ctx ctx;
> struct drm_plane *plane;
>- struct drm_crtc *crtc;
>- struct drm_crtc_state *crtc_state;
>+ struct drm_out_fence_state *fence_state = NULL;
> unsigned plane_mask;
> int ret = 0;
>- unsigned int i, j;
>+ unsigned int i, j, num_fences = 0;
>
> /* disallow for drivers not supporting atomic: */
> if (!drm_core_check_feature(dev, DRIVER_ATOMIC))
>@@ -1919,20 +2095,10 @@ int drm_mode_atomic_ioctl(struct drm_device *dev,
> drm_mode_object_unreference(obj);
> }
>
>- if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
>- for_each_crtc_in_state(state, crtc, crtc_state, i) {
>- struct drm_pending_vblank_event *e;
>-
>- e = create_vblank_event(dev, file_priv, NULL,
>- arg->user_data);
>- if (!e) {
>- ret = -ENOMEM;
>- goto out;
>- }
>-
>- crtc_state->event = e;
>- }
>- }
>+ ret = prepare_crtc_signaling(dev, state, arg, file_priv, &fence_state,
>+ &num_fences);
>+ if (ret)
>+ goto out;
>
> if (arg->flags & DRM_MODE_ATOMIC_TEST_ONLY) {
> /*
>@@ -1952,20 +2118,7 @@ int drm_mode_atomic_ioctl(struct drm_device *dev,
> out:
> drm_atomic_clean_old_fb(dev, plane_mask, ret);
>
>- if (ret && arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
>- /*
>- * TEST_ONLY and PAGE_FLIP_EVENT are mutually exclusive,
>- * if they weren't, this code should be called on success
>- * for TEST_ONLY too.
>- */
>-
>- for_each_crtc_in_state(state, crtc, crtc_state, i) {
>- if (!crtc_state->event)
>- continue;
>-
>- drm_event_cancel_free(dev, &crtc_state->event->base);
>- }
>- }
>+ complete_crtc_signaling(dev, state, fence_state, num_fences, ret);
>
> if (ret == -EDEADLK) {
> drm_atomic_state_clear(state);
>diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
>index 9b9881b..e8bc1ae 100644
>--- a/drivers/gpu/drm/drm_crtc.c
>+++ b/drivers/gpu/drm/drm_crtc.c
>@@ -274,6 +274,8 @@ int drm_crtc_init_with_planes(struct drm_device *dev, struct drm_crtc *crtc,
> if (drm_core_check_feature(dev, DRIVER_ATOMIC)) {
> drm_object_attach_property(&crtc->base, config->prop_active, 0);
> drm_object_attach_property(&crtc->base, config->prop_mode_id, 0);
>+ drm_object_attach_property(&crtc->base,
>+ config->prop_out_fence_ptr, 0);
> }
>
> return 0;
>@@ -434,6 +436,12 @@ static int drm_mode_create_standard_properties(struct drm_device *dev)
> return -ENOMEM;
> dev->mode_config.prop_in_fence_fd = prop;
>
>+ prop = drm_property_create_range(dev, DRM_MODE_PROP_ATOMIC,
>+ "OUT_FENCE_PTR", 0, U64_MAX);
>+ if (!prop)
>+ return -ENOMEM;
>+ dev->mode_config.prop_out_fence_ptr = prop;
>+
> prop = drm_property_create_object(dev, DRM_MODE_PROP_ATOMIC,
> "CRTC_ID", DRM_MODE_OBJECT_CRTC);
> if (!prop)
>diff --git a/include/drm/drm_atomic.h b/include/drm/drm_atomic.h
>index 331bb10..c0eaec7 100644
>--- a/include/drm/drm_atomic.h
>+++ b/include/drm/drm_atomic.h
>@@ -144,6 +144,7 @@ struct __drm_crtcs_state {
> struct drm_crtc *ptr;
> struct drm_crtc_state *state;
> struct drm_crtc_commit *commit;
>+ s64 __user *out_fence_ptr;
> };
>
> struct __drm_connnectors_state {
>diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
>index 0870de1..44571bc 100644
>--- a/include/drm/drm_crtc.h
>+++ b/include/drm/drm_crtc.h
>@@ -1264,6 +1264,12 @@ struct drm_mode_config {
> */
> struct drm_property *prop_in_fence_fd;
> /**
>+ * @prop_out_fence_ptr: Sync File fd pointer representing the
>+ * outgoing fences for a CRTC. Userspace should provide a pointer to a
>+ * value of type s64, and then cast that pointer to u64.
>+ */
>+ struct drm_property *prop_out_fence_ptr;
>+ /**
> * @prop_crtc_id: Default atomic plane property to specify the
> * &drm_crtc.
> */
>--
>2.5.5
>