Add back the removed documentation for drm_gem_open_ioctl.
This patch is submitted in response to [1].

[1] https://lore.kernel.org/linux-arm-msm/20200728085244.GY6419@phenom.ffwll.local/Signed-off-by: NSteve Cohen <cohens@codeaurora.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/1596000952-27621-1-git-send-email-cohens@codeaurora.org

A use-after-free in drm_gem_open_ioctl can happen if the
GEM object handle is closed between the idr lookup and
retrieving the size from said object since a local reference
is not being held at that point. Hold the local reference
while the object can still be accessed to fix this and
plug the potential security hole.
Signed-off-by: NSteve Cohen <cohens@codeaurora.org>
Cc: stable@vger.kernel.org
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/1595284250-31580-1-git-send-email-cohens@codeaurora.org

The .gem_print_info callback in struct drm_driver is obsolete and has
no users left. Remove it.
Signed-off-by: NThomas Zimmermann <tzimmermann@suse.de>
Suggested-by: NEmil Velikov <emil.velikov@collabora.com>
Reviewed-by: NEmil Velikov <emil.velikov@collabora.com>
Reviewed-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200605073247.4057-44-tzimmermann@suse.de

No real functional change, since this just converts an annoying Oops
into a more harmless WARNING backtrace. It's still a driver bug.
Acked-by: NThomas Zimmermann <tzimmermann@suse.de>
Tested-by: NBoris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200511093554.211493-3-daniel.vetter@ffwll.ch

Spelling out _unlocked for each and every driver is a annoying.
Especially if we consider how many drivers, do not know (or need to)
about the horror stories involving struct_mutex.

Just drop the suffix. It makes the API cleaner.

Done via the following script:

__from=drm_gem_object_put_unlocked
__to=drm_gem_object_put
for __file in $(git grep --name-only $__from); do
  sed -i  "s/$__from/$__to/g" $__file;
done

Pay special attention to the compat #define

v2: keep sed and #define removal separate

Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: NEmil Velikov <emil.velikov@collabora.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org> (v1)
Reviewed-by: NSteven Price <steven.price@arm.com>
Acked-by: NThomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20200515095118.2743122-14-emil.l.velikov@gmail.com

Vast majority of DRM (core and drivers) are struct_mutex free.

As such we have only a handful of cases where the locked helper should
be used. Make that stand out a little bit better.

Done via the following script:

__from=drm_gem_object_put
__to=drm_gem_object_put_locked

for __file in $(git grep --name-only --word-regexp $__from); do
  sed -i  "s/\<$__from\>/$__to/g" $__file;
done

Cc: Rob Clark <robdclark@gmail.com>
Cc: Sean Paul <sean@poorly.run>
Cc: linux-arm-msm@vger.kernel.org
Signed-off-by: NEmil Velikov <emil.velikov@collabora.com>
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Reviewed-by: NSteven Price <steven.price@arm.com>
Acked-by: NThomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20200515095118.2743122-12-emil.l.velikov@gmail.com

With earlier patch we removed the overhead so now we can lift the helper
into the header effectively folding it with __drm_object_put.

v2: drop struct_mutex references (Daniel)
Signed-off-by: NEmil Velikov <emil.velikov@collabora.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org> (v1)
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: NThomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20200515095118.2743122-11-emil.l.velikov@gmail.com

No drivers set the callback, so remove it all together.
Signed-off-by: NEmil Velikov <emil.velikov@collabora.com>
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Reviewed-by: NThomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200515095118.2743122-10-emil.l.velikov@gmail.com

The comment that struct_mutex must be held is misleading. It is only
required when .gem_free_object() is used.

Since that one is going with the next patches, drop the reference.
Signed-off-by: NEmil Velikov <emil.velikov@collabora.com>
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: NThomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20200515095118.2743122-7-emil.l.velikov@gmail.com

Use the drm_gem_object_put_unlocked in the documentation for
drm_gem_objects_lookup. The locked version of the helper should be used
solely by people who know exactly what they are doing.

Should prevent issues like ones adddressed with the next patch.
Signed-off-by: NEmil Velikov <emil.velikov@collabora.com>
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Acked-by: NThomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20200515095118.2743122-3-emil.l.velikov@gmail.com

If the "handles" allocation or the copy_from_user() fails then we leak
"objs".  It's supposed to be freed in panfrost_job_cleanup().

Fixes: c117aa4d ("drm: Add a drm_gem_objects_lookup helper")
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NEmil Velikov <emil.l.velikov@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200320132334.GC95012@mwanda

We might want to look into pushing this down into drm_mm_init, but
that would mean rolling out return codes to a pile of functions
unfortunately. So let's leave that for now.
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200323144950.3018436-24-daniel.vetter@ffwll.ch

Replace "pionter" with "pointer" in the drm_gem_handle_create description.

Changes in v2:
- Change subject text
Signed-off-by: NIgor Matheus Andrade Torrente <igormtorrente@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200317210339.2669-1-igormtorrente@gmail.com

[ 1715.899800] BUG: KCSAN: data-race in drm_gem_handle_create_tail / drm_gem_object_handle_put_unlocked
[ 1715.899838]
[ 1715.899861] write to 0xffff8881830f3604 of 4 bytes by task 7834 on cpu 1:
[ 1715.899896]  drm_gem_handle_create_tail+0x62/0x250
[ 1715.899927]  drm_gem_open_ioctl+0xc1/0x160
[ 1715.899956]  drm_ioctl_kernel+0xe4/0x120
[ 1715.899981]  drm_ioctl+0x297/0x4c7
[ 1715.900003]  ksys_ioctl+0x89/0xb0
[ 1715.900027]  __x64_sys_ioctl+0x42/0x60
[ 1715.900052]  do_syscall_64+0x6e/0x2c0
[ 1715.900079]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 1715.900100]
[ 1715.900119] read to 0xffff8881830f3604 of 4 bytes by task 8137 on cpu 0:
[ 1715.900149]  drm_gem_object_handle_put_unlocked+0x31/0x130
[ 1715.900180]  drm_gem_object_release_handle+0x93/0xe0
[ 1715.900208]  drm_gem_handle_delete+0x7b/0xe0
[ 1715.900235]  drm_gem_close_ioctl+0x61/0x80
[ 1715.900264]  drm_ioctl_kernel+0xe4/0x120
[ 1715.900291]  drm_ioctl+0x297/0x4c7
[ 1715.900316]  ksys_ioctl+0x89/0xb0
[ 1715.900340]  __x64_sys_ioctl+0x42/0x60
[ 1715.900363]  do_syscall_64+0x6e/0x2c0
[ 1715.900388]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200309120151.7675-1-chris@chris-wilson.co.uk

The fake offset is going to stay, so change the calling convention for
drm_gem_object_funcs.mmap to include the fake offset.  Update all users
accordingly.

Note that this reverts 83b8a6f2 ("drm/gem: Fix mmap fake offset
handling for drm_gem_object_funcs.mmap") and on top then adds the fake
offset to  drm_gem_prime_mmap to make sure all paths leading to
obj->funcs->mmap are consistent.

v3: move fake-offset tweak in drm_gem_prime_mmap() so we have this code
    only once in the function (Rob Herring).

Fixes: 83b8a6f2 ("drm/gem: Fix mmap fake offset handling for drm_gem_object_funcs.mmap")
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Rob Herring <robh@kernel.org>
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20191127092523.5620-2-kraxel@redhat.com

When mapping ttm objects via drm_gem_ttm_mmap() helper
drm_gem_mmap_obj() will take an object reference.  That gets
never released due to ttm having its own reference counting.

Fix that by dropping the gem object reference once the ttm mmap
completed (and ttm refcount got bumped).

For that to work properly the drm_gem_object_get() call in
drm_gem_ttm_mmap() must be moved so it happens before calling
obj->funcs->mmap(), otherwise the gem refcount would go down
to zero.

Fixes: 231927d9 ("drm/ttm: add drm_gem_ttm_mmap()")
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Tested-by: NThomas Zimmermann <tzimmermann@suse.de>
Link: http://patchwork.freedesktop.org/patch/msgid/20191113135612.19679-1-kraxel@redhat.com

Commit c40069cb ("drm: add mmap() to drm_gem_object_funcs")
introduced a GEM object mmap() hook which is expected to subtract the
fake offset from vm_pgoff. However, for mmap() on dmabufs, there is not
a fake offset.

To fix this, let's always call mmap() object callback with an offset of 0,
and leave it up to drm_gem_mmap_obj() to remove the fake offset.

TTM still needs the fake offset, so we have to add it back until that's
fixed.

Fixes: c40069cb ("drm: add mmap() to drm_gem_object_funcs")
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NRob Herring <robh@kernel.org>
Acked-by: NGerd Hoffmann <kraxel@redhat.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20191024191859.31700-1-robh@kernel.org

drm_gem_object_funcs->vm_ops alone can't handle everything which needs
to be done for mmap(), tweaking vm_flags for example.  So add a new
mmap() callback to drm_gem_object_funcs where this code can go to.

Note that the vm_ops field is not used in case the mmap callback is
present, it is expected that the callback sets vma->vm_ops instead.

Also setting vm_flags and vm_page_prot is the job of the new callback.
so drivers have more control over these flags.

drm_gem_mmap_obj() will use the new callback for object specific mmap
setup.  With this in place the need for driver-speific fops->mmap
callbacks goes away, drm_gem_mmap can be hooked instead.

drm_gem_prime_mmap() will use the new callback too to just mmap gem
objects directly instead of jumping though loops to make
drm_gem_object_lookup() and fops->mmap work.
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20191016115203.20095-2-kraxel@redhat.com

Be more consistent with the naming of the other DMA-buf objects.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/323401/

Panfrost has a need for pages allocated on demand via GPU page faults.
When releasing the pages, the only thing preventing using
drm_gem_put_pages() is needing to skip over unpopulated pages, so allow
for skipping over NULL struct page pointers.

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>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: NSteven Price <steven.price@arm.com>
Acked-by: NAlyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Reviewed-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NRob Herring <robh@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190808222200.13176-2-robh@kernel.org

This reverts commit 220df83a.

Turns out drm_gem_dumb_map_offset really only worked for the dumb buffer
case, so revert the name change.
Signed-off-by: NRob Herring <robh@kernel.org>
Signed-off-by: NSean Paul <sean@poorly.run>
Link: https://patchwork.freedesktop.org/patch/msgid/20190807145253.2037-2-sean@poorly.run

This reverts commit 415d2e9e.

Mandatory review was missing from this patch.
Acked-by: NMaxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: NSean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190807142101.251400-2-sean@poorly.run

Complete the abstraction of the ww_mutex inside the reservation object.

This allows us to add more handling and debugging to the reservation
object in the future.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/320761/

Do not rely on including drm.h from drm_file.h,
as the include in drm_file.h will be dropped.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Reviewed-by: NSean Paul <sean@poorly.run>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Eric Anholt <eric@anholt.net>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Rob Herring <robh@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190718161507.2047-7-sam@ravnborg.org

This reverts commit 220df83a.

Turns out drm_gem_dumb_map_offset really only worked for the dumb buffer
case, so revert the name change.
Signed-off-by: NRob Herring <robh@kernel.org>

drm_gem_dumb_map_offset() is a useful helper for non-dumb clients, so
rename it to remove the _dumb and add a comment that it can be used by
shmem clients.
Signed-off-by: NSteven Price <steven.price@arm.com>
Acked-by: NDaniel Vetter <daniel@ffwll.ch>
Signed-off-by: NRob Herring <robh@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190627155318.38053-2-steven.price@arm.com

It's tiny, already embedded, and setup/teardown cost is trivial.
Reviewed-by: NEric Anholt <eric@anholt.net>
Reviewed-by: NEmil Velikov <emil.velikov@collabora.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190614203615.12639-5-daniel.vetter@ffwll.ch

They're purely for internal use, not for drivers.

Cc: Noralf Trønnes <noralf@tronnes.org>
Cc: Christian König <christian.koenig@amd.com>
Reviewed-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190614203615.12639-3-daniel.vetter@ffwll.ch

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: NSam Ravnborg <sam@ravnborg.org>
Acked-by: NDaniel 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

Sphinx really wants colons after arguments :/

Fixes the following warnings:
drm_gem.c:1384: warning: Function parameter or member 'fence_array' not described in 'drm_gem_fence_array_add'
drm_gem.c:1384: warning: Function parameter or member 'fence' not described in 'drm_gem_fence_array_add'
drm_gem.c:1435: warning: Function parameter or member 'fence_array' not described in 'drm_gem_fence_array_add_implicit'
drm_gem.c:1435: warning: Function parameter or member 'obj' not described in 'drm_gem_fence_array_add_implicit'
drm_gem.c:1435: warning: Function parameter or member 'write' not described in 'drm_gem_fence_array_add_implicit'

Fixes: 5d5a179d ("drm: Add helpers for setting up an array of dma_fence dependencies.")
Cc: Eric Anholt <eric@anholt.net>
Cc: Qiang Yu <yuq825@gmail.com> (v1)
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>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NSean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190424204916.222155-1-sean@poorly.run

I needed to add implicit dependency support for v3d, and Rob Herring
has been working on it for panfrost, and I had recently looked at the
lima implementation so I think this will be a good intersection of
what we all want and simplify our scheduler implementations.

v2: Rebase on xa_limit_32b API change, and tiny checkpatch cleanups on
    the way in (unsigned int vs unsigned, extra return before
    EXPORT_SYMBOL_GPL)
Signed-off-by: NEric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20190401222635.25013-6-eric@anholt.net
Reviewed-and-tested-by: Qiang Yu <yuq825@gmail.com> (v1)

Similar to the single handle drm_gem_object_lookup(),
drm_gem_objects_lookup() takes an array of handles and returns an array
of GEM objects.

v2:
- Take the userspace pointer directly and allocate the array.
- Expand the function documentation.

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>
Cc: Daniel Vetter <daniel@ffwll.ch>
Acked-by: NAlyssa Rosenzweig <alyssa@rosenzweig.io>
Acked-by: NTomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: NRob Herring <robh@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190409205427.6943-3-robh@kernel.org

GEM defines DRM_FILE_PAGE_OFFSET_{START,SIZE} constants for the
mmap-able range of addresses. TTM can use them as well.
Signed-off-by: NThomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: NChristian König <christian.koenig@amd.com>
Acked-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Now that we have the reservation object in the GEM object, it's easy
to provide a helper for this common case.  Noticed while reviewing
panfrost and lima drivers.  This particular version came out of v3d,
which in turn was a copy from vc4.

v2: Fix kerneldoc warnings.
Signed-off-by: NEric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20190308161716.2466-2-eric@anholt.net
Acked-by: Rob Herring <robh@kernel.org> (v1)

Many users of drm_gem_object embed a struct reservation_object into
their subclassed struct, so let's add one to struct drm_gem_object.
This will allow removing the reservation object from the subclasses
and removing the ->gem_prime_res_obj callback.

With the addition, add a drm_gem_reservation_object_wait() helper
function for drivers to use in wait ioctls.

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>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: NRob Herring <robh@kernel.org>
Acked-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: NEric Anholt <eric@anholt.net>
Reviewed-by: NChristian Gmeiner <christian.gmeiner@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190202154158.10443-2-robh@kernel.orgSigned-off-by: NMaxime Ripard <maxime.ripard@bootlin.com>

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

The gem drivers use shmemfs to allocate backing storage for gem objects.
On Samsung Chromebook Plus, the drm/rockchip driver may call
rockchip_gem_get_pages -> drm_gem_get_pages -> shmem_read_mapping_page
to pin a lot of pages, breaking the page reclaim mechanism and causing
oom-killer invocation.

E.g. when the size of a zone is 3.9 GiB, the inactive_ratio is 5. If
active_anon / inactive_anon < 5 and all pages in the inactive_anon lru
are pinned, page reclaim would keep scanning inactive_anon lru without
reclaiming memory. It breaks page reclaim when the rockchip driver only
pins about 1/6 of the anon lru pages.

Mark these pinned pages as unevictable to avoid the premature oom-killer
invocation. See also similar patch on i915 driver [1].

[1]: https://patchwork.freedesktop.org/patch/msgid/20181106132324.17390-1-chris@chris-wilson.co.ukSigned-off-by: NKuo-Hsin Yang <vovoy@chromium.org>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190108074517.209860-1-vovoy@chromium.org

This adds an optional function table on GEM objects.
The main benefit is for drivers that support more than one type of
memory (shmem,vram,cma) for their buffers depending on the hardware it
runs on. With the callbacks attached to the GEM object itself, it is
easier to have core helpers for the the various buffer types. The driver
only has to make the decision about buffer type on GEM object creation
and all other callbacks can be handled by the chosen helper.

drm_driver->gem_prime_res_obj has not been added since there's a todo to
put a reservation_object into drm_gem_object.

v3: Add todo entry

v2: Drop drm_gem_object_funcs->prime_mmap in favour of
drm_gem_prime_mmap() (Daniel Vetter)

v1:
- drm_gem_object_funcs.map -> .prime_map let it only do PRIME mmap like
  the function it superseeds (Daniel Vetter)
- Flip around the if ladders and make obj->funcs the first choice
  highlighting the fact that this the new default way of doing it
  (Daniel Vetter)
Signed-off-by: NNoralf Trønnes <noralf@tronnes.org>
Acked-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: NChristian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181110145647.17580-4-noralf@tronnes.org

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: NChris 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

If the user has created a read-only object, they should not be allowed
to circumvent the write protection by using a GGTT mmapping. Deny it.

Also most machines do not support read-only GGTT PTEs, so again we have
to reject attempted writes. Fortunately, this is known a priori, so we
can at least reject in the call to create the mmap (with a sanity check
in the fault handler).

v2: Check the vma->vm_flags during mmap() to allow readonly access.
v3: Remove VM_MAYWRITE to curtail mprotect()

Testcase: igt/gem_userptr_blits/readonly_mmap*
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Jon Bloomfield <jon.bloomfield@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Matthew Auld <matthew.william.auld@gmail.com>
Cc: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Matthew Auld <matthew.william.auld@gmail.com> #v1
Reviewed-by: NJon Bloomfield <jon.bloomfield@intel.com>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180712185315.3288-4-chris@chris-wilson.co.uk