Hi Ville,
I still have some queries regarding the handling of aspect ratio flags
in getblob ioctl.
Please find below my responses inline.
On 2/1/2018 6:24 PM, Ville Syrjälä wrote:
On Thu, Feb 01, 2018 at 04:35:22PM +0530, Nautiyal, Ankit K wrote:
Hi Ville,
Appreciate your time and the suggestions.
Please find my response inline:
On 1/31/2018 6:39 PM, Ville Syrjälä wrote:
On Wed, Jan 31, 2018 at 12:04:52PM +0530, Nautiyal, Ankit K wrote:
On 1/30/2018 12:23 AM, Ville Syrjälä wrote:
On Fri, Jan 12, 2018 at 11:51:33AM +0530, Nautiyal, Ankit K wrote:
From: Ankit Nautiyal <ankit.k.nautiyal@xxxxxxxxx>
If the user mode does not support aspect-ratio, and requests for
a modeset, then the flag bits representing aspect ratio in the
given user-mode must be rejected.
Similarly, while preparing a user-mode from kernel mode, the
aspect-ratio info must not be given, if aspect-ratio is not
supported by the user.
This patch:
1. adds a new bit field aspect_ratio_allowed in drm_atomic_state,
which is set only if the aspect-ratio is supported by the user.
2. discards the aspect-ratio info from the user mode while
preparing kernel mode structure, during modeset, if the
user does not support aspect ratio.
3. avoids setting the aspect-ratio info in user-mode, while
converting user-mode from the kernel-mode.
Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@xxxxxxxxx>
V3: Addressed review comments from Ville:
-Do not corrupt the current crtc state by updating aspect ratio
on the fly.
---
drivers/gpu/drm/drm_atomic.c | 61 +++++++++++++++++++++++++++++++++++++++++---
drivers/gpu/drm/drm_crtc.c | 19 ++++++++++++++
include/drm/drm_atomic.h | 2 ++
3 files changed, 79 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index 69ff763..39313e2 100644
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -316,6 +316,35 @@ static s32 __user *get_out_fence_for_crtc(struct drm_atomic_state *state,
return fence_ptr;
}
+/**
+ * drm_atomic_allow_aspect_ratio_for_kmode
+ * @state: the crtc state
+ * @mode: kernel-internal mode, which is used to create a duplicate mode,
+ * with updated picture aspect ratio.
+ *
+ * Allow the aspect ratio info in the kernel mode only if aspect ratio is
+ * supported.
+ *
+ * RETURNS:
+ * kernel-internal mode with updated picture aspect ratio value.
+ */
+
+struct drm_display_mode*
+drm_atomic_allow_aspect_ratio_for_kmode(struct drm_crtc_state *state,
+ const struct drm_display_mode *mode)
+{
+ struct drm_atomic_state *atomic_state = state->state;
+ struct drm_display_mode *ar_kmode;
+
+ ar_kmode = drm_mode_duplicate(state->crtc->dev, mode);
+ /*
+ * If aspect ratio is not supported, set the picture aspect ratio as
+ * NONE.
+ */
+ if (atomic_state && !atomic_state->allow_aspect_ratio)
+ ar_kmode->picture_aspect_ratio = HDMI_PICTURE_ASPECT_NONE;
+ return ar_kmode;
+}
/**
* drm_atomic_set_mode_for_crtc - set mode for CRTC
@@ -341,7 +370,10 @@ int drm_atomic_set_mode_for_crtc(struct drm_crtc_state *state,
state->mode_blob = NULL;
if (mode) {
- drm_mode_convert_to_umode(&umode, mode);
+ struct drm_display_mode *ar_mode;
+
+ ar_mode = drm_atomic_allow_aspect_ratio_for_kmode(state, mode);
+ drm_mode_convert_to_umode(&umode, ar_mode);
This still looks sketchy.
I believe there are just two places where we need to filter out the
aspect ratio flags from the umode, namely the getblob and getcrtc
ioctls.
AFAIK The getblob ioctl can be called for edid blob, gamma, ctm blob,
etc. apart from the mode blob.
Is there any way to check from blob id (or by any other means),
if the data is for the mode, or edid, or gamma etc.
I think we'd have to somehow mark the mode blobs as special. Until we
have more need for cleaning up blobs before returning them to userspace
I think a simple flag should do. If we come up with more uses like this
then it might make sense to introduce some kind of optional filter
function for blobs.
If my understanding is correct,
1. To be able to do this, we need to change in uapi.
We should be fine with an internal flag. Obviously it won't be set
for blobs freshly created by userspace, but that's fine because we
do no other error checking for them either. The error checking will
happen when the user tries to actually use the blob.
I am not sure why getblob ioctl should even come into picture. (Perhaps
I am missing something).
As per my understanding:
If a userspace needs to set a mode, it will just create a blob with
drm_mode_mode_info,
and get the blob-id. This blob-id would be supplied to
drm_mode_atomic_ioctl as a crtc
property mode_id.
At the kernel side, the crtc property mode_id is set by looking-up for
mode blob from blob id.
I am doing the change in the user mode aspect-ratio flags at this junction.
As far as getblob ioctl is concerned, if the user does call getblob
ioctl for getting mode blob from
the blob id, it will receive the same mode blob, with same aspect ratio
info which the user had
created using create blob ioctl. If it does want to use the blob, it has
to come through the
drm_mode_atomic_ioctl way, where aspect ratio flags are handled.
2. Whenever the userspace creates a blob for mode, the new flag/class
for blob type needs to be set.
Do you think that it's worth the effort?
If we can check that, I can make sure that aspect-ratio flags are taken
care of, if the blob is for mode,
and the aspect ratio is not supported.
And for checking the user input I think we should probably just
stick that into drm_mode_convert_umode(). Looks like we never call
that from anywhere but the atomic/setprop and setcrtc paths with
a non-NULL argument.
I *think* those three places should be sufficient to cover everything.
Agreed. Infact I tried to do that first, but the only problem we have
here, is that, the file_priv
which has the aspect ratio capability information is not supplied to the
drm_mode_convert_umode()
or the functions calling, drm_mode_conver_umode(). At best we have
drm_crtc_state.
Simply passing the file_priv down would seem like the most obvious
solution.
This means we have to make change in various drivers and we have to pull
the file_priv
parameter three levels down. Should we think of a better way for doing this?
Coccinelle is pretty good at modifying function parameters.
Thanks for pointing out Coccinelle, will defintely try that out.
But my question here is whether we really want to drag the file_priv
from drm_mode_atomic_ioctl --> drm_mode_atomic_set_property -->
drm_atomic_crtc_set_property --> drm_mode_set_mode_prop_for_crtc-->
drm_mode_convert_umode.
Instead, I tried to add a new field (allow_aspect_ratio) in
drm_crtc_state which is
already passed from the drm_mode_atomic_ioctl all the way to
drm_mode_convert_umode.
-Regards
Ankit
I have added an aspect ratio allowed flag in drm_crtc_state->state so
that its available in the
functions calling drm_mode_convert_umode.
I am open to suggestion to avoid adding a new flag in drm_atomic_state,
if there is a better
way to let the drm_mode_convert_umode( ) know that user supports aspect
ratio capability.
state->mode_blob =
drm_property_create_blob(state->crtc->dev,
sizeof(umode),
@@ -349,10 +381,11 @@ int drm_atomic_set_mode_for_crtc(struct drm_crtc_state *state,
if (IS_ERR(state->mode_blob))
return PTR_ERR(state->mode_blob);
- drm_mode_copy(&state->mode, mode);
+ drm_mode_copy(&state->mode, ar_mode);
state->enable = true;
DRM_DEBUG_ATOMIC("Set [MODE:%s] for CRTC state %p\n",
- mode->name, state);
+ ar_mode->name, state);
+ drm_mode_destroy(state->crtc->dev, ar_mode);
} else {
memset(&state->mode, 0, sizeof(state->mode));
state->enable = false;
@@ -436,6 +469,25 @@ drm_atomic_replace_property_blob_from_id(struct drm_device *dev,
}
/**
+ * drm_atomic_allow_aspect_ratio_for_umode
+ * @state: the crtc state
+ * @umode: userspace mode, whose aspect ratio flag bits are to be updated.
+ *
+ * Allow the aspect ratio info in the userspace mode only if aspect ratio is
+ * supported.
+ */
+void
+drm_atomic_allow_aspect_ratio_for_umode(struct drm_crtc_state *state,
+ struct drm_mode_modeinfo *umode)
+{
+ struct drm_atomic_state *atomic_state = state->state;
+
+ /* Reset the aspect ratio flags if aspect ratio is not supported */
+ if (atomic_state && !atomic_state->allow_aspect_ratio)
+ umode->flags &= (~DRM_MODE_FLAG_PIC_AR_MASK);
+}
+
+/**
* drm_atomic_crtc_set_property - set property on CRTC
* @crtc: the drm CRTC to set a property on
* @state: the state object to update with the new property value
@@ -464,6 +516,9 @@ int drm_atomic_crtc_set_property(struct drm_crtc *crtc,
else if (property == config->prop_mode_id) {
struct drm_property_blob *mode =
drm_property_lookup_blob(dev, val);
+ drm_atomic_allow_aspect_ratio_for_umode(state,
+ (struct drm_mode_modeinfo *)
+ mode->data);
ret = drm_atomic_set_mode_prop_for_crtc(state, mode);
drm_property_blob_put(mode);
return ret;
diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index f0556e6..a2d34fa 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -425,6 +425,13 @@ int drm_mode_getcrtc(struct drm_device *dev,
drm_modeset_lock(&crtc->mutex, NULL);
if (crtc->state) {
if (crtc->state->enable) {
+ /*
+ * If the aspect-ratio is not required by the,
+ * userspace, do not set the aspect-ratio flags.
+ */
+ if (!file_priv->aspect_ratio_allowed)
+ crtc->state->mode.picture_aspect_ratio =
+ HDMI_PICTURE_ASPECT_NONE;
These would still clobber the current crtc state. So definitely don't
want to do this.
Alright, so alternative way of doing this will be:
Avoid changing the crtc->state->mode.picture_aspect_ratio i.e kernel
mode structure,
but set the aspect ratio flags in the usermode to none, after calling the
drm_mode_convert_to_umode().
Will take care of this in the next patchset.
I gave a thought about it again. As you have mentioned earlier that
get_crtc is one of the
place where the user mode aspect ratio flags must be filtered out, is
this what you have
in mind. I hope I did not misunderstand.
Changing the usermode aspect ratio flag bits, without change in the
picture_aspect_ratio
kernel mode will not result in both structures out of sync?
I don't think that should really matter. I suppose we might get one
extra modeset when the user feeds that mode back via setcrtc/atomic, but
meh. And actually the aspect ratio should only affect the infoframe, so
we should be able to eventually eliminate that extra modeset and just
update the infoframe instead.
drm_mode_convert_to_umode(&crtc_resp->mode, &crtc->state->mode);
crtc_resp->mode_valid = 1;
@@ -435,6 +442,13 @@ int drm_mode_getcrtc(struct drm_device *dev,
crtc_resp->x = crtc->x;
crtc_resp->y = crtc->y;
if (crtc->enabled) {
+ /*
+ * If the aspect-ratio is not required by the,
+ * userspace, do not set the aspect-ratio flags.
+ */
+ if (!file_priv->aspect_ratio_allowed)
+ crtc->mode.picture_aspect_ratio =
+ HDMI_PICTURE_ASPECT_NONE;
drm_mode_convert_to_umode(&crtc_resp->mode, &crtc->mode);
crtc_resp->mode_valid = 1;
@@ -610,6 +624,11 @@ int drm_mode_setcrtc(struct drm_device *dev, void *data,
goto out;
}
+ /* If the user does not ask for aspect ratio, reset the aspect
+ * ratio bits in the usermode.
+ */
+ if (!file_priv->aspect_ratio_allowed)
+ crtc_req->mode.flags &= (~DRM_MODE_FLAG_PIC_AR_MASK);
ret = drm_mode_convert_umode(mode, &crtc_req->mode);
if (ret) {
DRM_DEBUG_KMS("Invalid mode\n");
diff --git a/include/drm/drm_atomic.h b/include/drm/drm_atomic.h
index 1c27526..130dad9 100644
--- a/include/drm/drm_atomic.h
+++ b/include/drm/drm_atomic.h
@@ -237,6 +237,7 @@ struct __drm_private_objs_state {
* @ref: count of all references to this state (will not be freed until zero)
* @dev: parent DRM device
* @allow_modeset: allow full modeset
+ * @allow_aspect_ratio: allow the aspect ratio info to be passes to user
* @legacy_cursor_update: hint to enforce legacy cursor IOCTL semantics
* @async_update: hint for asynchronous plane update
* @planes: pointer to array of structures with per-plane data
@@ -256,6 +257,7 @@ struct drm_atomic_state {
struct drm_device *dev;
bool allow_modeset : 1;
+ bool allow_aspect_ratio : 1;
bool legacy_cursor_update : 1;
bool async_update : 1;
struct __drm_planes_state *planes;
--
2.7.4
_______________________________________________
dri-devel mailing list
dri-devel@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/dri-devel
Regards,
Ankit
_______________________________________________
dri-devel mailing list
dri-devel@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/dri-devel
