This is pure evil. Userspace, I'm looking at you SNA, repacks batch
buffers on the fly after generation as they are being passed to the
kernel for execution. These batches also contain self-referenced
relocations as a single buffer encompasses the state commands, kernels,
vertices and sampler. During generation the buffers are placed at known
offsets within the full batch, and then the relocation deltas (as passed
to the kernel) are tweaked as the batch is repacked into a smaller buffer.
This means that userspace is passing negative relocations deltas, which
subsequently wrap to large values if the batch is at a low address. The
GPU hangs when it then tries to use the large value as a base for its
address offsets, rather than wrapping back to the real value (as one
would hope). As the GPU uses positive offsets from the base, we can
treat the relocation address as the minimum address read by the GPU.
For the upper bound, we trust that userspace will not read beyond the
end of the buffer.

So, how do we fix negative relocations from wrapping? We can either
check that every relocation looks valid when we write it, and then
position each object such that we prevent the offset wraparound, or we
just special-case the self-referential behaviour of SNA and force all
batches to be above 256k. Daniel prefers the latter approach.

This fixes a GPU hang when it tries to use an address (relocation +
offset) greater than the GTT size. The issue would occur quite easily
with full-ppgtt as each fd gets its own VM space, so low offsets would
often be handed out. However, with the rearrangement of the low GTT due
to capturing the BIOS framebuffer, it is already affecting kernels 3.15
onwards. I think only IVB+ is susceptible to this bug, but the workaround
should only kick in rarely, so it seems sensible to always apply it.

v3: Use a bias for batch buffers to prevent small negative delta relocations
from wrapping.

v4 from Daniel:
- s/BIAS/BATCH_OFFSET_BIAS/
- Extract eb_vma_misplaced/i915_vma_misplaced since the conditions
  were growing rather cumbersome.
- Add a comment to eb_get_batch explaining why we do this.
- Apply the batch offset bias everywhere but mention that we've only
  observed it on gen7 gpus.
- Drop PIN_OFFSET_FIX for now, that slipped in from a feature patch.

v5: Add static to eb_get_batch, spotted by 0-day tester.

Testcase: igt/gem_bad_reloc
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=78533
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> (v3)
Cc: stable@vger.kernel.org
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We only want to modifiy a single field in the userspace view of the
execbuffer command buffer, so explicitly change that rather than copy
everything back again.

This serves two purposes:

1. The single fields are much cheaper to copy (constant size so the
copy uses special case code) and much smaller than the whole array.

2. We modify the array for internal use that need to be masked from
the user.

Note: We need this backported since without it the next bugfix will
blow up when userspace recycles batchbuffers and relocations.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: stable@vger.kernel.org
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Up until now, contexts had one (and only one) backing object that was
used by the hardware to save/restore render ring contexts (via the
MI_SET_CONTEXT command). Other rings did not have or need this, so
our i915_hw_context struct had a 1:1 relationship with a a real HW
context.

With Logical Ring Contexts and Execlists, this is not possible anymore:
all rings need a backing object, and it cannot be reused. To prepare
for that, rename our contexts to the more generic term intel_context.

No functional changes.
Signed-off-by: NOscar Mateo <oscar.mateo@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

In the upcoming patches we plan to break the correlation between
engine command streamers (a.k.a. rings) and ringbuffers, so it
makes sense to refactor the code and make the change obvious.

No functional changes.
Signed-off-by: NOscar Mateo <oscar.mateo@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Adding stuff at the bottom is really no how this should be done, since
that's the place for ums/dri dungeons.

This was added in

commit a8ebba75
Author: Zhao Yakui <yakui.zhao@intel.com>
Date:   Thu Apr 17 10:37:40 2014 +0800

    drm/i915: Use the coarse ping-pong mechanism based on drm fd to dispatch the BSD command on BDW GT3

Also add a note to prevent this from happening again - people really
should be less lazy and take more time to look for a good home of
their new driver-global state.

Cc: Imre Deak <imre.deak@intel.com>
Cc: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

More fallout from

commit c8725f3d
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Mon Mar 17 12:21:55 2014 +0000

    drm/i915: Do not call retire_requests from wait_for_rendering

is that we can completely fill all of memory using small objects, such
that we exhaust the filp space, and spend all of our time evicting
objects from the aperture. As such, we never fill the ring, and never
trigger the last resort flushing in

commit 1cf0ba14
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Mon May 5 09:07:33 2014 +0100

    drm/i915: Flush request queue when waiting for ring space

and so all the requests are left active and the objects keep that last
active reference. Eventually the system comes to a halt as it runs out
of memory.

The impact is mainly limited to test cases as regular userspace will
trigger retirement by manually checking whether an object is active.

Testcase: igt/gem_lut_handle
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=78724Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Tested-by: NGuo Jinxian <jinxianx.guo@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Somehow UXA submits a completely bogus DR4 value since essentially
forever. It was originally introduced in

commit bade7d7d2505a10a8a7d24b084aff9742e2d6d64
Author: Eric Anholt <eric@anholt.net>
Date:   Fri Jun 6 14:03:25 2008 -0700

    Use the DRM for submitting batchbuffers when available.

and dutifully copied around ever since. Since we want to keep the
general dirt catching around just special case the UXA value.

This regression was introduced in

commit 9cb34664
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Thu Apr 24 08:09:11 2014 +0200

    drm/i915: Catch dirt in unused execbuffer fields

Comment from Chris' review:

"To be fair, it is a sensible value if one supposes a Region style API to
cliprects. Under that API, DR[14] define the extents of the clip region,
and ((0,0), (0,0)) [DR1==DR4==0] would mean all clipped, do not draw
anything."

v2: Pimp commit message a bit and remove the double space.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=78494
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jörg Otte <jrg.otte@gmail.com>
Acked-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

All the rest of the code to enable this is in my branch. Without my
branch, hitting > 32b offsets is impossible. The code has always
"supported" 64b, but it's never actually been run of tested. This change
doesn't actually fix anything. [1] I am not sure why X won't work yet. I
do not get hangs or obvious errors.

There are 3 fixes grouped together here. First is to remove the
hardcoded 0 for the upper dword of the relocation. The next fix is to
use a 64b value for target_offset. The final fix is to not directly
apply target_offset to reloc->delta. reloc->delta is part of ABI, and so
we cannot change it. As it stands, 32b is enough to represent everything
we're interested in representing anyway. The main problem is, we cannot
add greater than 32b values to it directly.

[1] Almost all of intel-gpu-tools is not yet ready to test 64b
relocations. There are a few places that expect 32b values for offsets
and these all won't work.

Cc: Rafael Barbalho <rafael.barbalho@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Previously, our code only had a 32b offset value for where the
batchbuffer starts. With full PPGTT, and 64b canonical GPU address
space, that is an insufficient value. The code to expand is pretty
straight forward, and only one platform needs to do anything with the
extra bits.
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NRafael Barbalho <rafael.barbalho@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

A common issue we have is that retiring requests causes recursion
through GTT manipulation or page table manipulation which we can only
handle at very specific points. However, to maintain internal
consistency (enforced through our sanity checks on write_domain at
various points in the GEM object lifecycle) we do need to retire the
object prior to marking it with a new write_domain, and also clear the
write_domain for the implicit flush following a batch.

Note that this then allows the unbound objects to still be on the active
lists, and so care must be taken when removing objects from unbound lists
(similar to the caveats we face processing the bound lists).

v2: Fix i915_gem_shrink_all() to handle updated object lifetime rules,
by refactoring it to call into __i915_gem_shrink().

v3: Missed an object-retire prior to changing cache domains in
i915_gem_object_set_cache_leve()

v4: Rebase
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Tested-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NBrad Volkin <bradley.d.volkin@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The BDW GT3 has two independent BSD rings, which can be used to process the
video commands. To be simpler, it is transparent to user-space driver/middle.
Instead the kernel driver will decide which ring is to dispatch the BSD video
command.

As every BSD ring is powerful, it is enough to dispatch the BSD video command
based on the drm fd. In such case it can play back video stream while encoding
another video stream. The coarse ping-pong mechanism is used to determine
which BSD ring is used to dispatch the BSD video command.

V1->V2: Follow Daniel's comment and use the simple ping-pong mechanism.
This is only to add the support of dual BSD rings on BDW GT3 machine.
The further optimization will be considered in another patch set.

V2->V3: Follow Daniel's comment to use the struct_mutext instead of
atomic_t during determining which ring can be used to dispatch Video command.
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NZhao Yakui <yakui.zhao@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Signed-off-by: NZhao Yakui <yakui.zhao@intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We need to make sure that userspace keeps on following the contract,
otherwise we won't be able to use the reserved fields at all.

v2: Add DRM_DEBUG (Chris)

Testcase: igt/gem_exec_params/*-dirt
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

A bit tricky since 0 is also a valid constant ...

v2: Add DRM_DEBUG (Chris)

Testcase: igt/gem_exec_params/rel-constants-*
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Currently we catch it, but silently succeed. Our userspace is
better than this.

v2: Add DRM_DEBUG (Chris)

Testcase: igt/gem_exec_params/sol-reset-*
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

If we always initialize kref for the context, even if we are using fake
contexts for hangstats when there is no hw support, we can forgo the
dance to dereference the ctx->obj and inspect whether we are permitted
to use kref inside i915_gem_context_reference() and _unreference().

My ulterior motive here is to improve the debugging of a use-after-free
of ctx->obj. This patch avoids the dereference here and instead forces
the assertion checks associated with kref.

v2: Refactor the fake contexts to being even more like the real
contexts, so that there is much less duplicated and special case code.

v3: Tweaks.
v4: Tweaks, minor.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=76671Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Tested-by: Nlu hua <huax.lu@intel.com>
Cc: Ben Widawsky <benjamin.widawsky@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
[Jani: tiny change to backport to drm-intel-fixes.]
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

I opted to do this instead of grabbing the context reference after
eb_create since eb_create can potentially call the shrinker, and that
makes things very complicated. This simple patch balances the ref count
without requiring a great deal of review to make sure the shrinker path
is safe.

Theoretically (by design) the shrinker can end up destroying a context,
which enforces the reasoning for doing the fix this way instead of
moving the reference to later in the function.

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

Remove the rest of the references to drm_i915_private_t. No functional
changes.
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
[danvet: Drop hunk in i915_cmd_parser.c]
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>

One side-effect of the introduction of ppgtt was that we needed to
rebind the object into the appropriate vm (and global gtt in some
peculiar cases). For simplicity this was done twice for every object on
every call to execbuffer. However, that adds a tremendous amount of CPU
overhead (rewriting all the PTE for all objects into WC memory) per
draw. The fix is to push all the decision about which vm to bind into
and when down into the low-level bind routines through hints rather than
performing the bind unconditionally in the execbuffer routine.

Note that this is a regression introduced in the full ppgtt feature
branch, before this we've only done re-bound objects when the relevant
has_(aliasing_ppgtt|global_gtt)_mapping flag was clear. But since
that's per-object and not per-vma that optimization broke.

v2: Split out prep work and unrelated changes.

v3: Bring back functional change around PIN_GLOBAL that I've
accidentally split out.

v4: Remove the temporary hack for the old binding logic to avoid
bisection issues.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=72906
Tested-by: jianx.zhou@intel.com
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> (v1)
Cc: Ben Widawsky <benjamin.widawsky@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

With abitrary pin flags it makes sense to split out a "please bind
this into global gtt" from the "please allocate in the mappable
range".

Use this unconditionally in our global gtt pin helper since this is
what its callers want. Later patches will drop PIN_MAPPABLE where it's
not strictly needed.
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Anything more than just one bool parameter is just a pain to read,
symbolic constants are much better.

Split out from Chris' vma-binding rework patch.

v2: Undo the behaviour change in object_pin that Chris spotted.

v3: Split out misplaced hunk to handle set_cache_level errors,
spotted by Jani.

v4: Keep the current over-zealous binding logic in the execbuffer code
working with a quick hack while the overall binding code gets shuffled
around.

v5: Reorder the PIN_ flags for more natural patch splitup.

v6: Pull out the PIN_GLOBAL split-up again.

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

With 20+ module parameters, I think referring to them via a struct
improves clarity over just having a bunch of globals. While at it, move
the parameter initialization and definitions into a new file
i915_params.c to reduce clutter in i915_drv.c.

Apart from the ill-named i915_enable_rc6, i915_enable_fbc and
i915_enable_ppgtt parameters, for which we lose the "i915_" prefix
internally, the module parameters now look the same both on the kernel
command line and in code. For example, "i915.modeset".

The downsides of the change are losing static on a couple of variables
and not having the initialization and module_param_named() right next to
each other. On the other hand, all module parameters are now defined in
one place at i915_params.c. Plus you can do this to find all module
parameter references:

$ git grep "i915\." -- drivers/gpu/drm/i915

v2:
- move the definitions into a new file
- s/i915_params/i915/
- make i915_try_reset i915.reset, for consistency
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This address will be used to verify panel CRC for test and
validation purposes.
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@gmail.com>
[danvet: Fix whitespace fail.]
Acked-by: NDave Airlie <airlied@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

While trying to find a random -EINVAL from a failing test, I noticed we
had a few hard to follow return values.

The first two hunks in this patch replace completely useless
initialization of ret. The last several hunks help to distinguish
between altering 'return ret' and 'return <ERROR>'
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Without this fix the ioctls silently succeeded (but actually did
nothing).

It makes all the code which calls into this function way too confusing.

v2: Fix destroy IOCTL as well

v3: Clarify the other two callers of i915_gem_context_get() to never
check for NULL. (Mika)

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=72903Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Testcase: igt/gem_ctx_exec/basic
[danvet: Fix up the commit message and actually bother to mention the
testcase this fixes.]
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This means something different and is only relevant for gen6 and the
reason why we cant use anything else than aliasing ppgtt there.

Note that the currently implemented logic for secure batches is
broken: Userspace wants the buffer both in ppgtt (for self-referencing
relocations) and in ggtt (for priveledge operations).

This is the same issue the command parser is also facing.
Unfortunately our coverage for corner-cases of self-referencing
batches is spotty.

Note that this will break vsync'ed Xv and DRI2 copies.
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Doesn't make sense. Spotted while fixing an issue Chris
noticed in the same area.
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This reverts the abi-change from

commit 67e3d297
Author: Ben Widawsky <ben@bwidawsk.net>
Date:   Fri Dec 6 14:11:01 2013 -0800

    drm/i915: Permit contexts on all rings

We don't actually need this, only the internal changes to allow
contexts on all rings for the purpose of ppgtt switching are required.
And I'm not sure whether this is the right thing to do given some of
the hw features in the pipeline.

Also, new abi needs userspace patches as a proof-of-need, which is
completely lacking here.
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

As with processes which run on the CPU, the goal of multiple VMs is to
provide process isolation. Specific to GEN, there is also the ability to
map more objects per process (2GB each instead of 2Gb-2k total).

For the most part, all the pipes have been laid, and all we need to do
is remove asserts and actually start changing address spaces with the
context switch. Since prior to this we've converted the setting of the
page tables to a streamed version, this is quite easy.

One important thing to point out (since it'd been hotly contested) is
that with this patch, every context created will have it's own address
space (provided the HW can do it).

v2: Disable BDW on rebase

NOTE: I tried to make this commit as small as possible. I needed one
place where I could "turn everything on" and that is here. It could be
split into finer commits, but I didn't really see much point.

Cc: Eric Anholt <eric@anholt.net>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We need to have the address space when reserving space for the objects.
Since the address space and context are tied together, and reserve
occurs before context switch (for good reason), we must lookup our
context earlier in the process.

This leaves some room for optimizations where we no longer need to use
ctx_id in certain places. This will be addressed in a subsequent patch.

Important tricky bit:
Because slow relocations during execbuffer drop struct_mutex

Perhaps it would be best to acquire the reference when we get the
context, but I'll save that for another day (note I have written the
patch before, and I found the changes required to be uglier than this).

Note that since we currently access everything via context id, and not
the data structure this is fine, though not desirable. The next change
attempts to get the context only once via the context ID idr lookup, and
as such, the following can happen:

CTX-A is created, refcount = 1
CTX-A execbuf, mutex dropped
close IOCTL called on CTX-A, refcount = 0
CTX-A resumes in execbuf.

v2: Rebased on top of
commit b6359918
Author: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Date:   Wed Oct 30 15:44:16 2013 +0200

    drm/i915: add i915_get_reset_stats_ioctl

v3: Rebased on top of
commit 25b3dfc8
Author: Mika Westerberg <mika.westerberg@linux.intel.com>
Date:   Tue Nov 12 11:57:30 2013 +0200

Author: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Date:   Tue Nov 26 16:14:33 2013 +0200

    drm/i915: check context reset stats before relocations
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

If we want to use contexts in more abstract terms (specifically with
PPGTT in mind), we need to allow them to be specified for any ring.

Since the upcoming patches will bring about the use of multiple address
spaces, and each ring needs to have an address space programmed (which
we intend to do at context switch time), we can no longer only use RCS.

With multiple rings having a last context, we must now unreference these
contexts.

NOTE: This commit requires an update to intel-gpu-tools to make it not
fail.

v2: Rebased with some logical conflicts.
Squashed in the context fini refcount patch
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The only place we were using it was for GEN6, which won't have PPGTT
support anyway (ie. the VM is always the same). To clear things up,
(it only added confusion for me since it doesn't allow us to assert
vma->vm is what we always want, when just looking at the code).
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

To sum up what goes on here, we abstract the vma binding, similarly to
the previous object binding. This helps for distinguishing legacy
binding, versus modern binding. To keep the code churn as minimal as
possible, I am leaving in insert_entries(). It serves as the per
platform pte writing basically. bind_vma and insert_entries do share a
lot of similarities, and I did have designs to combine the two, but as
mentioned already... too much churn in an already massive patchset.

What follows are the 3 commits which existed discretely in the original
submissions. Upon rebasing on Broadwell support, it became clear that
separation was not good, and only made for more error prone code. Below
are the 3 commit messages with all their history.

drm/i915: Add bind/unbind object functions to VMA
drm/i915: Use the new vm [un]bind functions
drm/i915: reduce vm->insert_entries() usage

drm/i915: Add bind/unbind object functions to VMA

As we plumb the code with more VM information, it has become more
obvious that the easiest way to deal with bind and unbind is to simply
put the function pointers in the vm, and let those choose the correct
way to handle the page table updates. This change allows many places in
the code to simply be vm->bind, and not have to worry about
distinguishing PPGTT vs GGTT.

Notice that this patch has no impact on functionality. I've decided to
save the actual change until the next patch because I think it's easier
to review that way. I'm happy to squash the two, or let Daniel do it on
merge.

v2:
Make ggtt handle the quirky aliasing ppgtt
Add flags to bind object to support above
Don't ever call bind/unbind directly for PPGTT until we have real, full
PPGTT (use NULLs to assert this)
Make sure we rebind the ggtt if there already is a ggtt binding.  This
happens on set cache levels.
Use VMA for bind/unbind (Daniel, Ben)

v3: Reorganize ggtt_vma_bind to be more concise and easier to read
(Ville). Change logic in unbind to only unbind ggtt when there is a
global mapping, and to remove a redundant check if the aliasing ppgtt
exists.

v4: Make the bind function a bit smarter about the cache levels to avoid
unnecessary multiple remaps. "I accept it is a wart, I think unifying
the pin_vma / bind_vma could be unified later" (Chris)
Removed the git notes, and put version info here. (Daniel)

v5: Update the comment to not suck (Chris)

v6:
Move bind/unbind to the VMA. It makes more sense in the VMA structure
(always has, but I was previously lazy). With this change, it will allow
us to keep a distinct insert_entries.
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>

drm/i915: Use the new vm [un]bind functions

Building on the last patch which created the new function pointers in
the VM for bind/unbind, here we actually put those new function pointers
to use.

Split out as a separate patch to aid in review. I'm fine with squashing
into the previous patch if people request it.

v2: Updated to address the smart ggtt which can do aliasing as needed
Make sure we bind to global gtt when mappable and fenceable. I thought
we could get away without this initialy, but we cannot.

v3: Make the global GTT binding explicitly use the ggtt VM for
bind_vma(). While at it, use the new ggtt_vma helper (Chris)

At this point the original mailing list thread diverges. ie.

v4^:
use target_obj instead of obj for gen6 relocate_entry
vma->bind_vma() can be called safely during pin. So simply do that
instead of the complicated conditionals.
Don't restore PPGTT bound objects on resume path
Bug fix in resume path for globally bound Bos
Properly handle secure dispatch
Rebased on vma bind/unbind conversion
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>

drm/i915: reduce vm->insert_entries() usage

FKA: drm/i915: eliminate vm->insert_entries()

With bind/unbind function pointers in place, we no longer need
insert_entries. We could, and want, to remove clear_range, however it's
not totally easy at this point. Since it's used in a couple of place
still that don't only deal in objects: setup, ppgtt init, and restore
gtt mappings.

v2: Don't actually remove insert_entries, just limit its usage. It will
be useful when we introduce gen8. It will always be called from the vma
bind/unbind.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> (v1)
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Whilst looking up the objects required for an execbuffer, an untimely
allocation failure in creating the vma results in the object being
unreferenced from two lists. The ownership during the lookup is meant to
be moved from the list of objects being looked to the vma, and this
double unreference upon error results in a use-after-free.

Fixes regression from
commit 27173f1f
Author: Ben Widawsky <ben@bwidawsk.net>
Date:   Wed Aug 14 11:38:36 2013 +0200

    drm/i915: Convert execbuf code to use vmas

Based on the fix by Ben Widawsky.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: stable@vger.kernel.org
[danvet: Bikeshed the crucial comment above the ownership transfer as
discussed on irc.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

If I add code to enable runtime PM on my Haswell machine, start a
desktop environment, then enable runtime PM, these functions will
complain that they're trying to read/write registers while the
graphics card is suspended.

v2: - Simplify i915_gem_fault changes.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@gmail.com>
[danvet: Drop the hunk in i915_hangcheck_elapsed, it's the wrong thing
to do.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Doing it early prevents moving and relocating objects in vain
for contexts that won't get any GPU time.
Reported-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

As the execbuffer dispatch grows ever more complex and involves multiple
stages of moving objects into the aperture, we need to take greater care
that we do not evict our execbuffer objects prior to dispatch. This is
relatively simple as we can just keep the objects pinned for not just
the relocation but until we are finished.

One such example is the possibility of the context switch causing an
eviction or hitting the shrinker in order to fit its object into the
aperture.

Link: http://lists.freedesktop.org/archives/intel-gfx/2013-November/036166.htmlReported-by: N"Siluvery, Arun" <arun.siluvery@intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Ben Widawsky <benjamin.widawsky@intel.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: stable@vger.kernel.org
Acked-by: NBen Widawsky <ben@bwidawsk.net>
Tested-by: NBen Widawsky <ben@bwidawsk.net>
[danvet: Add the additional explanations from Chris to the commit
message.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>