drm/drm_property: make replace_property_blob_from_id a DRM helper

Place it in drm_property where drm_property_replace_blob and
drm_property_lookup_blob live. Then we can use the DRM helper for
driver-specific KMS properties too.

Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Melissa Wen <mwen@igalia.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm: property: Replace strncpy() with strscpy_pad()

strncpy() is widely regarded as unsafe due to the fact that it may leave
the destination string without a nul-termination when the source string
size is too large. When compiling the kernel with W=1, the gcc warns
about this:

drivers/gpu/drm/drm_property.c: In function ‘drm_property_create’:
drivers/gpu/drm/drm_property.c:130:2: warning: ‘strncpy’ specified bound 32 equals destination size [-Wstringop-truncation]
130 | strncpy(property->name, name, DRM_PROP_NAME_LEN);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

There are three occurrences of strncpy() in drm_property.c. None of them
are actually unsafe, as the very next line forces nul-termination of the
destination buffer. The warning is thus a false positive, but adds noise
to the kernel log. It can easily be silenced by using strscpy_pad()
instead. Do so.

One of the three occurrences, in drm_property_add_enum(), fills a char
array that is later copied to userspace with copy_to_user() in
drm_mode_getproperty_ioctl(). To avoid leaking kernel data,
strscpy_pad() is required. Similarly, a second occurrence, in
drm_mode_getproperty_ioctl(), copies the string to an ioctl data buffer
that isn't previously zero'ed, to strscpy_pad() is also required. The
last occurrence, in drm_property_create(), would be safe to replace with
strscpy(), as the destination buffer is copied to userspace with
strscpy_pad(). However, given that this isn't in a hot path, let's avoid
future data leaks in case someone copies the whole char array blindly.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm: Fix typo in comments

fix typo for drm

v1->v2:
respin with the change "iff ==> implies that"

Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210730132729.376-1-caihuoqing@baidu.com

drm: Few typo fixes

s/instatiated/instantiated/
s/unreference/unreferenced/

Signed-off-by: Bhaskar Chowdhury <unixbhaskar@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210318103739.27849-1-unixbhaskar@gmail.com

drm: limit to INT_MAX in create_blob ioctl

The hardened usercpy code is too paranoid ever since commit 6a30afa8c1fb
("uaccess: disallow > INT_MAX copy sizes")

Code itself should have been fine as-is.

Link: http://lkml.kernel.org/r/20191106164755.31478-1-daniel.vetter@ffwll.ch
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reported-by: syzbot+fb77e97ebf0612ee6914@syzkaller.appspotmail.com
Fixes: 6a30afa8c1fb ("uaccess: disallow > INT_MAX copy sizes")
Cc: Kees Cook <keescook@chromium.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drm: drop use of drmP.h in drm/*

The use of the drmP.h header file is deprecated.
Remove use from all files in drm/*
so people do not look there and follow a bad example.

Build tested allyesconfig,allmodconfig on x86, arm etc.
Including alpha that is as always more challenging than
the rest.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: Sean Paul <sean@poorly.run>
Cc: David Airlie <airlied@linux.ie>
Link: https://patchwork.freedesktop.org/patch/msgid/20190526173535.32701-8-sam@ravnborg.org

drm: Trivial comment grammar cleanups

Most of these are just cases where code comments used contractions
(it's, who's) where they actually mean to use a possessive pronoun (its,
whose) or vice-versa.

Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20190202012326.20096-1-matthew.d.roper@intel.com

drm: Differentiate the lack of an interface from invalid parameter

If the ioctl is not supported on a particular piece of HW/driver
combination, report ENOTSUP (aka EOPNOTSUPP) so that it can be easily
distinguished from both the lack of the ioctl and from a regular invalid
parameter.

v2: Across all the kms ioctls we had a mixture of reporting EINVAL,
ENODEV and a few ENOTSUPP (most where EINVAL) for a failed
drm_core_check_feature(). Update everybody to report ENOTSUPP.

v3: ENOTSUPP is an internal errno! It's value (524) does not correspond
to a POSIX errno, the one we want is ENOTSUP. However,
uapi/asm-generic/errno.h doesn't include ENOTSUP but man errno says

"ENOTSUP and EOPNOTSUPP have the same value on Linux,
but according to POSIX.1 these error values should be
distinct."

so use EOPNOTSUPP as its equivalent.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> #v2
Link: https://patchwork.freedesktop.org/patch/msgid/20180913192050.24812-1-chris@chris-wilson.co.uk

drm: Use kvzalloc for allocating blob property memory

The property size may be controlled by userspace, can be large (I've
seen failure with order 4, i.e. 16 pages / 64 KB) and doesn't need to be
physically contiguous.

Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180629142710.2069-1-michel@daenzer.net
Cc: stable@vger.kernel.org

drm: Don't pass the index to drm_property_add_enum()

drm_property_add_enum() can calculate the index itself just fine,
so no point in having the caller pass it in.

Cc: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: nouveau@lists.freedesktop.org
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180316190420.26734-1-ville.syrjala@linux.intel.com
Reviewed-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>

Revert "drm: Use a flexible array member for blob property data"

Using a flexible array for the blob data was a mistake by me. It
forces all users of the blob data to cast blob->data to something
else. void* is clearly superior so let's go back to the original
scheme.

Not a clean revert as the code has moved.

This reverts commit d63f5e6bf6f2a1573ea39c9937cdf5ab0b3a4b77.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180223192506.29992-1-ville.syrjala@linux.intel.com
Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm: Reject bad property flag combinations

Pimp drm_property_type_valid() to check for more fails with the
property flags. Also make the check before adding the property,
and bail out if things look bad.

Since we're now chekcing for more than the type let's also
change the function name to drm_property_flags_valid().

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180306164849.2862-6-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm: Make property flags u32

The property flags are part of the uabi and we have 32 bits for them.
Pass them around as u32 internally as well, instead of a signed int.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180306164849.2862-5-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm: WARN when trying to add enum value > 63 to a bitmask property

Enum values >63 with a bitmask property is a programmer error. WARN
when someone is attempting this.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180306164849.2862-3-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm: WARN when trying add enum values to non-enum/bitmask properties

Trying to add enum values to non-enum/bitmask properties is a
programmer mistake. WARN to make sure the developers notice
their mistake.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180306164849.2862-2-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm: Reject replacing property enum values

If the property already has the enum value WARN and bail.
Replacing enum values doesn't make sense to me.

Throw out the pointless list_empty() while at it.

Cc: Daniel Vetter <daniel@ffwll.ch>
Suggested-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180306164849.2862-1-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm: Check property/enum name length

Reject requests to add properties/enums with an overly long name.
Previously we would have just silently truncated the string and exposed
it userspace.

v2: drm_property_create() returns a pointer

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180302140300.31110-1-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm: Don't create properties without names

Creating a property that doesn't have a name makes no sense to me. Don't
allow it.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180302132544.12491-1-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm: Pass struct drm_file * to __drm_mode_object_find [v2]

This will allow __drm_mode_object_file to be extended to perform
access control checks based on the file in use.

v2: Also fix up vboxvideo driver in staging

[airlied: merging early as this is an API change]

Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drm: rename, adjust and export drm_atomic_replace_property_blob

The function has little to do with atomic, it's just where it has so
far been needed. So, rename it to drm_property_replace_blob, move it
to drm_property.c and export it.

Change the semantics to return whether the blob was replaced instead
of using an extra argument for that.

Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170713162538.22788-2-peda@axentia.se

drm: Fix get_property logic fumble

Yet again I've proven that I can't negate conditions :(

Testcase: igt/kms_properties/get_property-sanity
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Fixes: eb8eb02ed850 ("drm: Drop modeset_lock_all from the getproperty ioctl")
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Sean Paul <seanpaul@chromium.org>
Reported-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170410115445.13829-1-daniel.vetter@ffwll.ch

drm: Drop modeset_lock_all from the getproperty ioctl

Properties, i.e. the struct drm_property specifying the type and value
range of a property, not the instantiation on a given object, are
invariant over the lifetime of a driver.

Hence no locking at all is needed, we can just remove it.

While at it give the function some love and simplify it, to get it
under the 80 char limit:
- Straighten the loops to reduce the nesting.
- use u64_to_user_ptr casting helper
- use put_user for fixed u64 copies.

Note there's a small behavioural change in that we now copy parts of
the values to userspace if the arrays are a bit too small. Since
userspace will immediately retry anyway, this doesn't matter.

Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170403083304.9083-7-daniel.vetter@ffwll.ch

drm: Introduce drm_property_blob_{get,put}()

For consistency with other reference counting APIs in the kernel, add
drm_property_blob_get() and drm_property_blob_put() to reference count
DRM blob properties.

Compatibility aliases are added to keep existing code working. To help
speed up the transition, all the instances of the old functions in the
DRM core are already replaced in this commit.

A semantic patch is provided that can be used to convert all drivers to
the new helpers.

Reviewed-by: Sean Paul <seanpaul@chromium.org>
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170228144643.5668-7-thierry.reding@gmail.com

drm: Introduce drm_mode_object_{get,put}()

For consistency with other reference counting APIs in the kernel, add
drm_mode_object_get() and drm_mode_object_put() to reference count DRM
mode objects.

Compatibility aliases are added to keep existing code working. To help
speed up the transition, all the instances of the old functions in the
DRM core are already replaced in this commit.

A semantic patch is provided that can be used to convert all drivers to
the new helpers.

Reviewed-by: Sean Paul <seanpaul@chromium.org>
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170228144643.5668-3-thierry.reding@gmail.com

drm: Rename drm_mode_object_get()

Subsequent patches will introduce reference counting APIs that are more
consistent with similar APIs throughout the Linux kernel. These APIs use
the _get() and _put() suffixes and will collide with this existing
function.

Rename the function to drm_mode_object_add() which is a slightly more
accurate description of what it does. Also the kerneldoc for this
function gives an indication that it's badly named because it doesn't
actually acquire a reference to anything.

Reviewed-by: Sean Paul <seanpaul@chromium.org>
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170228144643.5668-2-thierry.reding@gmail.com

drm/kms-core: Use recommened kerneldoc for struct member refs

I just learned that &struct_name.member_name works and looks pretty
even. It doesn't (yet) link to the member directly though, which would
be really good for big structures or vfunc tables (where the
per-member kerneldoc tends to be long).

Also some minor drive-by polish where it makes sense, I read a lot
of docs ...

v2: Review from Eric.

Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Eric Engestrom <eric.engestrom@imgtec.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170125062657.19270-4-daniel.vetter@ffwll.ch

drm/doc: use preferred struct reference in kernel-doc

sed -e 's/\( \* .*\)struct &\([_a-z]*\)/\1\&struct \2/' -i

Originally I wasnt a friend of this style because I thought a
line-break between the "&struct" and "foo" part would break it. But a
quick test shows that " * &struct \n * foo\n" works pefectly well with
current kernel-doc. So time to mass-apply these changes!

Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1483044517-5770-6-git-send-email-daniel.vetter@ffwll.ch

drm: Use u64_to_user_ptr() helper for blob ioctls

Remove the ugly sparse casts by using the helper u64_to_user_ptr()
instead.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161127170910.29106-1-chris@chris-wilson.co.uk

drm/doc: Fix links in drm_property.c

One of the functions was missing () to make the autolinks work,
unfortunately copy-pasted a few times all over.

Cc: Manasi Navare <manasi.d.navare@intel.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161123192327.28819-1-daniel.vetter@ffwll.ch

Revert "drm: Unify handling of blob and object properties"

This reverts commit 77953bd136d2a70bca2dc93b3ccda07a2b37076f.

This causes a kernel panic when trying to assign a blob to a property,
and has obviously never been tested.

Fixes: 77953bd136d2 ("drm: Unify handling of blob and object properties")
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Tested-by: Liu Ying <gnuiyl@gmail.com>
Acked-by: Daniel Stone <daniels@collabora.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/8c0d3482-1bb5-6a15-b105-6bda2b31b5dc@linux.intel.com

drm/doc: Polish docs for drm_property&drm_property_blob

- remove kerneldoc for drm-internal functions
- drm_property_replace_global_blob isn't actually atomic, and doesn't
need to be. Update docs&comments to match
- document all the types and try to link things a bit better
- nits all over

v2: Appease checkpatch in the moved code (Archit)

Reviewed-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20160829082757.17913-9-daniel.vetter@ffwll.ch

drm: Unify handling of blob and object properties

They work exactly the same now, after the refcounting unification a bit
ago. The only reason they're distinct is backwards compat with existing
userspace.

Cc: Daniel Stone <daniels@collabora.com>
Reviewed-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20160829082757.17913-8-daniel.vetter@ffwll.ch

drm: Extract drm_property.[hc]

This just contains the base property classes and all the code to
handle blobs. I think for any kind of standardized/shared properties
it's better to have separate files - this is fairly big already as-is.

v2: resurrect misplaced hunk (Daniel Stone)

Cc: Daniel Stone <daniel@fooishbar.org>
Reviewed-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20160829082757.17913-7-daniel.vetter@ffwll.ch