We used to protect minor-lookup and setup by the global drm lock. To
continue our attempts of dropping drm_global_mutex, this patch makes the
minor management independent of it. Furthermore, we make it all atomic and
switch to spin-locks instead of a mutex.

Now that minor-lookup is independent, we also move the
"drm_is_unplugged()" test into the minor-lookup path. There is no reason
to ever return a minor for unplugged objects, so keep that logic internal.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>

We can significantly simplify this helper by using plain multiplication.
Note that we converted the minor-type to an enum earlier so this didn't
work before.

We also fix a minor range-bug here: the limit argument of idr_alloc() is
*exclusive*, not inclusive, so we should use 64 instead of 63 as offset.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>

Properly name goto-labels, remove empty lines and use DRM_ERROR if
possible.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>

Whenever we access minor->device, we are in a minor->kdev->...->fops
callback so the minor->kdev pointer *must* be valid. Thus, simply use
minor->kdev->devt instead of minor->device and remove the redundant field.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

No need to check for DEBUGFS, we already have dummy-fallbacks in our
headers.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

drm_get_minor() no longer allocates objects, and drm_unplug_minor() is now
the exact reverse of it. Rename it to _register/unregister() so their
name actually says what they do.

Furthermore, remove the direct minor-ptr and instead pass the minor-type.
This way we know the actual slot of the minor and can reset it if
required.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

_put/get() are used for ref-counting, which we clearly don't do here.
Rename it to _free() and also use the common drm_minor_* prefix.
Furthermore, avoid passing the minor directly but instead use the type
like the other functions do, this allows us to reset the slot.

We also drop the redundant call to drm_unplug_minor() as drm_minor_free()
is only used from paths were that has already be called.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Instead of waiting for device-registration, we now allocate minor-objects
during device allocation. The minors are not registered or assigned an ID.
This is still postponed to device-registration.

While at it, remove the superfluous output-parameter in drm_get_minor().

The reason for this early allocation is to make
dev->primary/control/render available atomically. So once the device is
alive, all of them are already set and we never have the situation where
one of them is set after another (they're either NULL or set, but never
changed). This will eventually allow us to reduce minor-ID allocation to
one base-ID instead of a single ID for each.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Instead of accessing drm_minors_idr directly, this adds a small helper to
hide the internals. This will help us later to remove the drm_global_mutex
requirement for minor-lookup.

Furthermore, this also makes sure that minor->dev is always valid and
takes a reference-count to the device as long as the minor is used in an
open-file. This way, "struct file*"->private_data->dev is guaranteed to be
valid (which it has to, as we cannot reset it).
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Lets not trick ourselves into thinking "drm_device" objects are not
ref-counted. That's just utterly stupid. We manage "drm_minor" objects on
each drm-device and each minor can have an unlimited number of open
handles. Each of these handles has the drm_minor (and thus the drm_device)
as private-data in the file-handle. Therefore, we may not destroy
"drm_device" until all these handles are closed.

It is *not* possible to reset all these pointers atomically and restrict
access to them, and this is *not* how this is done! Instead, we use
ref-counts to make sure the object is valid and not freed.

Note that we currently use "dev->open_count" for that, which is *exactly*
the same as a reference-count, just open coded. So this patch doesn't
change any semantics on DRM devices (well, this patch just introduces the
ref-count, anyway. Follow-up patches will replace open_count by it).

Also note that generic VFS revoke support could allow us to drop this
ref-count again. We could then just synchronously disable any fops->xy()
calls. However, this is not the case, yet, and no such patches are
in sight (and I seriously question the idea of dropping the ref-cnt
again).
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>

The drm_open_helper() function is only used internally for drm_open() so
we can safely pass in the minor-object directly instead of the minor-id.
This way, we avoid the additional minor IDR lookup, which we already do
twice in drm_stub_open() and drm_open().
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

There is no need to initialize this variable, so drop it. Otherwise, the
compiler won't warn if we use it unintialized.
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>

Lets make sure some basic expressions are always true:
  bpp != NULL
  width != NULL
  height != NULL
  stride = bpp * width < 2^32
  size = stride * height < 2^32
  PAGE_ALIGN(size) < 2^32

At least the udl driver doesn't check for multiplication-overflows, so
lets just make sure it will never happen. These checks allow drivers to do
any 32bit math without having to test for mult-overflows themselves.

The two divisions might hurt performance a bit, but dumb_create() is only
used for scanout-buffers, so that should be fine. We could use 64bit math
to avoid the divisions, but that may be slow on 32bit machines.. Or maybe
there should just be a "safe_mult32()" helper, which currently doesn't
exist (I think?).
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>

All drivers currently need to clean up the vma-node manually. There is no
fancy logic involved so lets just clean it up unconditionally. The
vma-manager correctly catches multiple calls so we are fine.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>

Remove double-whitespace and wrong indentation.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>

Probably a typo.. we obviously need "(bpp + 7) / 8" instead of
"(bpp + 1) / 8". Unlikely to be hit in any sane code, but lets be safe.
Use DIV_ROUND_UP() to avoid the problem entirely and make the core more
readable.
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>

We need to call dma_buf_end_cpu_access() in case a damage-request.
Unlikely, but might happen during device unplug.
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>

- Standardized on "Returns:" Block.
- Sprinkle missing kerneldoc over all exported functions and all
  ioctls.
- Add a stern warning that driver's really shouldn't use
  drm_mode_group_init_legacy_group.
- Usual attempt at more consistency.
- Add warnings that drm_mode_object_get/put don't do refcounting,
  despite what the names might lead to believe.
- Try to clarify the framebuffer setup/cleanup functions wrt driver
  private framebuffers - I've fallen recently over this when reviewing
  i915 fbdev patches.
- Align function parameters where the kerneldoc has been updated.
- Most of the drm_get_*_name functions aren't thread safe. Add stern
  warnings where this is the case.

Since a lot of the functions in drm_crtc.c are boilerplate to handle
properties and create default sets of them it might be useful to
extract all that code into a new file drm_property.c. Especially since
properties will be used a lot more in the future.
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Most of this is newly added kerneldoc for the hotplug and output
polling code. But I've also thrown in a bit lesser polish, most of it
is tuning down the shouting RETURN: headers.

Overview documentation for the output probing and mode setting support
code will be added in later patches.
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

No driver cares, and it should generally work. Add a big comment
when drivers can't use this for recompense.
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

- It yells.
- WARNing about incorrect locking is harder to ignore, so better
  than kerneldoc.
- Since those have been written per-crtc locks were added ...

So remove them and replace them by appropriate WARNs.
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Rightfully no driver ever checked this - it can't fail.
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

- Tune down yelling RETURNS.
- OCD align all the parameters the same.
- Add missing kerneldoc, which also means that we need to include the
  kerneldoc from the drm_modes.h header now.
- Add missing Returns: sections.
- General polish and clarification - especially the kerneldoc for the
  mode creation helpers seems to have been some good specimen of
  copypasta gone wrong.

All actual code changes have all been extracted into prep patches
since there was simply too much to polish.

v2: More polish for the command line modeline functions.
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Totally unused and actually redundant with maxX for display mode
validation. The fb helper otoh needs to check pitch limits,
but that is delegated into drivers instead.
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

It never fails and no one ever checked anyway.
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

There's a neat FIXME asking whether this is really need. I'd
say really no.
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

I want to also include kerneldoc from the header (for static inline
functions and structs), but fishing the right pieces out of a giant
header is a real pain. So split things out.

Note that it's not a really clean header with sane include orders, but
given's drm historical knack for giant headers detangling this is a
major task.

v2: Also extract struct drm_cmdline_mode.
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Makes more sense and gives better grouping in the DocBook function
reference sections. To make this possible we need to expose two
functions from drm_crtc.c though. To avoid further namespace pollution
in the system wide headers create a new internal header for such drm
internal symbols.

I expect that longer-term we'll add tons more, but since my goal here
is to polish the kerneldoc that's for another day.
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

There's not really any value in stating that no locking is needed. And
even if the comment is useful, a check for the right mutex at the
beginning of the function is better since that can't be ingored as
easily as a bit of documentation.

Note that drm_mode_probed_add in drm_crtc.c is also changed, the next
patch will move this into drm_modes.c

v2: Don't add locking WARN_ONs where it is not strictly required (i.e.
the two functions to validate/prune mode lists).
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

And clean it up so that there's no kerneldoc warnings. There's still a
lot to do with this one here.
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

It's only used by imx, and that one gets it wrong - there's no need
to deteach the encoder before removing it.

And really, neither current drm modesetting code nor all the userspace
we have can handle dynamic changes in the set of possible encoders for
a given connector. So let's just remove this before someone starts
doing something really nasty with it.

As a plus, one less kerneldoc comment to write.

Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

While at it do a tiny bit of interface cleanup and convert boolean
return values to bool. With this patch all exported functions and inline
helpers which are part of the drm_mm public interface are documented.

Also drop superflous extern function modifiers since most of drm_mm.h
doesn't use them - more consistent that way.
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

kerneldoc polish will follow in the next patch.

Hopefully documenting the lru scan support a bit better spurs someone
to give this a shot in the ttm eviction code. At least in i915 it
helped quite a lot with memory thrashing on platforms where eviction
was (we've fixed that too meanwhile) fairly expensive.
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This was missed in

commit c700c67b
Author: David Herrmann <dh.herrmann@gmail.com>
Date:   Sat Jul 27 13:39:28 2013 +0200

    drm/mm: remove unused API

Cc: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

For giant hilarity the DocBook reference overview is only generated
when in a level 2 section, not in a level 3 section. So we need to
move this up a bit as a side-by-side section to the main PRIME
documentation.

Whatever.

To have a complete set of references add the missing kerneldoc for all
functions exported to modules with the exception of the file private
init/destroy functions - drivers have no business calling those, so
let's just drop the EXPORT_SYMBOL instead.

Also reflow the function parameters to align correctly and break at 80
chars - my OCD couldn't stand them while writing the kerneldoc ;-)
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Stumbled over while reviewing all occurences in the DRM doc talking
about suspend/resume.
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Fairly incomplete, but at least a start.
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

v2: Also do s/RETURNS/Returns/, less yelling in docs is always good.
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Chris suggested to split things up a bit into the different parts of
the driver and also sort it all correctly, with the hope that we're
trying to organize things a bit better eventually. It should also
help newcomers to orient themselves a bit better.

v2:
- Move intel_pm.c to the core - to make things perfect we should split
  out the modeset related pm features (psr/fbc) into a separate file.
  Maybe something Rodrigo can do once the PSR patches have settled.

- Split the modesetting sections into core and encoders/outputs.
  intel_ddi.c is a bit funky since it has core hsw+ support and ddi
  output support. Whatever.

v3: Failed to git add ...

v4: Really go ocd, i.e. spelling fix in a comment from Jani.

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The command parser scans batch buffers submitted via execbuffer ioctls before
the driver submits them to hardware. At a high level, it looks for several
things:

1) Commands which are explicitly defined as privileged or which should only be
   used by the kernel driver. The parser generally rejects such commands, with
   the provision that it may allow some from the drm master process.
2) Commands which access registers. To support correct/enhanced userspace
   functionality, particularly certain OpenGL extensions, the parser provides a
   whitelist of registers which userspace may safely access (for both normal and
   drm master processes).
3) Commands which access privileged memory (i.e. GGTT, HWS page, etc). The
   parser always rejects such commands.

See the overview comment in the source for more details.

This patch only implements the logic. Subsequent patches will build the tables
that drive the parser.

v2: Don't set the secure bit if the parser succeeds
Fail harder during init
Makefile cleanup
Kerneldoc cleanup
Clarify module param description
Convert ints to bools in a few places
Move client/subclient defs to i915_reg.h
Remove the bits_count field

OTC-Tracker: AXIA-4631
Change-Id: I50b98c71c6655893291c78a2d1b8954577b37a30
Signed-off-by: NBrad Volkin <bradley.d.volkin@intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
[danvet: Appease checkpatch.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>