drm/i915: limit the async bind to bind_async_flags

If the vm doesn't request async binding, like for example with the dpt,
then we should be able to skip the async path and avoid calling
i915_vm_loc

drm/i915: limit the async bind to bind_async_flags

If the vm doesn't request async binding, like for example with the dpt,
then we should be able to skip the async path and avoid calling
i915_vm_lock_objects() altogether. Currently if we have a moving fence
set for the BO(even though it might have signalled), we still take the
async patch regardless of the bind_async setting, and then later still
end up just doing i915_gem_object_wait_moving_fence() anyway.

Alternatively we would need to add dummy scratch object which can be
locked, just for the dpt.

Suggested-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220304095934.925036-2-matthew.auld@intel.com

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drm/i915: Remove the vma refcount

Now that i915_vma_parked() is taking the object lock on vma destruction,
and the only user of the vma refcount, i915_gem_object_unbind()
also takes the object lock,

drm/i915: Remove the vma refcount

Now that i915_vma_parked() is taking the object lock on vma destruction,
and the only user of the vma refcount, i915_gem_object_unbind()
also takes the object lock, remove the vma refcount.

v3: Documentation update.

Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Niranjana Vishwanathapura <niranjana.vishwanathapura@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220304082641.308069-3-thomas.hellstrom@linux.intel.com

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drm/i915: Remove the vm open count

vms are not getting properly closed. Rather than fixing that,
Remove the vm open count and instead rely on the vm refcount.

The vm open count existed solely to br

drm/i915: Remove the vm open count

vms are not getting properly closed. Rather than fixing that,
Remove the vm open count and instead rely on the vm refcount.

The vm open count existed solely to break the strong references the
vmas had on the vms. Now instead make those references weak and
ensure vmas are destroyed when the vm is destroyed.

Unfortunately if the vm destructor and the object destructor both
wants to destroy a vma, that may lead to a race in that the vm
destructor just unbinds the vma and leaves the actual vma destruction
to the object destructor. However in order for the object destructor
to ensure the vma is unbound it needs to grab the vm mutex. In order
to keep the vm mutex alive until the object destructor is done with
it, somewhat hackishly grab a vm_resv refcount that is released late
in the vma destruction process, when the vm mutex is no longer needed.

v2: Address review-comments from Niranjana
- Clarify that the struct i915_address_space::skip_pte_rewrite is a hack
and should ideally be replaced in an upcoming patch.
- Remove an unneeded continue in clear_vm_list and update comment.

v3:
- Documentation update
- Commit message formatting

Co-developed-by: Niranjana Vishwanathapura <niranjana.vishwanathapura@intel.com>
Signed-off-by: Niranjana Vishwanathapura <niranjana.vishwanathapura@intel.com>
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Niranjana Vishwanathapura <niranjana.vishwanathapura@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220304082641.308069-2-thomas.hellstrom@linux.intel.com

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drm/i915: Clarify vma lifetime

It's unclear what reference the initial vma kref reference refers to.
A vma can have multiple weak references, the object vma list,
the vm's bound list and the GT's cl

drm/i915: Clarify vma lifetime

It's unclear what reference the initial vma kref reference refers to.
A vma can have multiple weak references, the object vma list,
the vm's bound list and the GT's closed_list, and the initial vma
reference can be put from lookups of all these lists.

With the current implementation this means
that any holder of yet another vma refcount (currently only
i915_gem_object_unbind()) needs to be holding two of either
*) An object refcount,
*) A vm open count
*) A vma open count

in order for us to not risk leaking a reference by having the
initial vma reference being put twice.

Address this by re-introducing i915_vma_destroy() which removes all
weak references of the vma and *then* puts the initial vma refcount.
This makes a strong vma reference hold on to the vma unconditionally.

Perhaps a better name would be i915_vma_revoke() or i915_vma_zombify(),
since other callers may still hold a refcount, but with the prospect of
being able to replace the vma refcount with the object lock in the near
future, let's stick with i915_vma_destroy().

Finally this commit fixes a race in that previously i915_vma_release() and
now i915_vma_destroy() could destroy a vma without taking the vm->mutex
after an advisory check that the vma mm_node was not allocated.
This would race with the ungrab_vma() function creating a trace similar
to the below one. This was fixed in one of the __i915_vma_put() callsites
in
commit bc1922e5d349 ("drm/i915: Fix a race between vma / object destruction and unbinding")
but although not seemingly triggered by CI, that
is not sufficient. This patch is needed to fix that properly.

[823.012188] Console: switching to colour dummy device 80x25
[823.012422] [IGT] gem_ppgtt: executing
[823.016667] [IGT] gem_ppgtt: starting subtest blt-vs-render-ctx0
[852.436465] stack segment: 0000 [#1] PREEMPT SMP NOPTI
[852.436480] CPU: 0 PID: 3200 Comm: gem_ppgtt Not tainted 5.16.0-CI-CI_DRM_11115+ #1
[852.436489] Hardware name: Intel Corporation Alder Lake Client Platform/AlderLake-P DDR5 RVP, BIOS ADLPFWI1.R00.2422.A00.2110131104 10/13/2021
[852.436499] RIP: 0010:ungrab_vma+0x9/0x80 [i915]
[852.436711] Code: ef e8 4b 85 cf e0 e8 36 a3 d6 e0 8b 83 f8 9c 00 00 85 c0 75 e1 5b 5d 41 5c 41 5d c3 e9 d6 fd 14 00 55 53 48 8b af c0 00 00 00 <8b> 45 00 85 c0 75 03 5b 5d c3 48 8b 85 a0 02 00 00 48 89 fb 48 8b
[852.436727] RSP: 0018:ffffc90006db7880 EFLAGS: 00010246
[852.436734] RAX: 0000000000000000 RBX: ffffc90006db7598 RCX: 0000000000000000
[852.436742] RDX: ffff88815349e898 RSI: ffff88815349e858 RDI: ffff88810a284140
[852.436748] RBP: 6b6b6b6b6b6b6b6b R08: ffff88815349e898 R09: ffff88815349e8e8
[852.436754] R10: 0000000000000001 R11: 0000000051ef1141 R12: ffff88810a284140
[852.436762] R13: 0000000000000000 R14: ffff88815349e868 R15: ffff88810a284458
[852.436770] FS: 00007f5c04b04e40(0000) GS:ffff88849f000000(0000) knlGS:0000000000000000
[852.436781] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[852.436788] CR2: 00007f5c04b38fe0 CR3: 000000010a6e8001 CR4: 0000000000770ef0
[852.436797] PKRU: 55555554
[852.436801] Call Trace:
[852.436806] <TASK>
[852.436811] i915_gem_evict_for_node+0x33c/0x3c0 [i915]
[852.437014] i915_gem_gtt_reserve+0x106/0x130 [i915]
[852.437211] i915_vma_pin_ww+0x8f4/0xb60 [i915]
[852.437412] eb_validate_vmas+0x688/0x860 [i915]
[852.437596] i915_gem_do_execbuffer+0xc0e/0x25b0 [i915]
[852.437770] ? deactivate_slab+0x5f2/0x7d0
[852.437778] ? _raw_spin_unlock_irqrestore+0x50/0x60
[852.437789] ? i915_gem_execbuffer2_ioctl+0xc6/0x2c0 [i915]
[852.437944] ? init_object+0x49/0x80
[852.437950] ? __lock_acquire+0x5e6/0x2580
[852.437963] i915_gem_execbuffer2_ioctl+0x116/0x2c0 [i915]
[852.438129] ? i915_gem_do_execbuffer+0x25b0/0x25b0 [i915]
[852.438300] drm_ioctl_kernel+0xac/0x140
[852.438310] drm_ioctl+0x201/0x3d0
[852.438316] ? i915_gem_do_execbuffer+0x25b0/0x25b0 [i915]
[852.438490] __x64_sys_ioctl+0x6a/0xa0
[852.438498] do_syscall_64+0x37/0xb0
[852.438507] entry_SYSCALL_64_after_hwframe+0x44/0xae
[852.438515] RIP: 0033:0x7f5c0415b317
[852.438523] Code: b3 66 90 48 8b 05 71 4b 2d 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 41 4b 2d 00 f7 d8 64 89 01 48
[852.438542] RSP: 002b:00007ffd765039a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
[852.438553] RAX: ffffffffffffffda RBX: 000055e4d7829dd0 RCX: 00007f5c0415b317
[852.438562] RDX: 00007ffd76503a00 RSI: 00000000c0406469 RDI: 0000000000000017
[852.438571] RBP: 00007ffd76503a00 R08: 0000000000000000 R09: 0000000000000081
[852.438579] R10: 00000000ffffff7f R11: 0000000000000246 R12: 00000000c0406469
[852.438587] R13: 0000000000000017 R14: 00007ffd76503a00 R15: 0000000000000000
[852.438598] </TASK>
[852.438602] Modules linked in: snd_hda_codec_hdmi i915 mei_hdcp x86_pkg_temp_thermal snd_hda_intel snd_intel_dspcfg drm_buddy coretemp crct10dif_pclmul crc32_pclmul snd_hda_codec ttm ghash_clmulni_intel snd_hwdep snd_hda_core e1000e drm_dp_helper ptp snd_pcm mei_me drm_kms_helper pps_core mei syscopyarea sysfillrect sysimgblt fb_sys_fops prime_numbers intel_lpss_pci smsc75xx usbnet mii
[852.440310] ---[ end trace e52cdd2fe4fd911c ]---

v2: Fix typos in the commit message.

Fixes: 7e00897be8bf ("drm/i915: Add object locking to i915_gem_evict_for_node and i915_gem_evict_something, v2.")
Fixes: bc1922e5d349 ("drm/i915: Fix a race between vma / object destruction and unbinding")
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220222133209.587978-1-thomas.hellstrom@linux.intel.com

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drm/i915: add I915_BO_ALLOC_GPU_ONLY

If the user doesn't require CPU access for the buffer, then
ALLOC_GPU_ONLY should be used, in order to prioritise allocating in the
non-mappable portion of LMEM,

drm/i915: add I915_BO_ALLOC_GPU_ONLY

If the user doesn't require CPU access for the buffer, then
ALLOC_GPU_ONLY should be used, in order to prioritise allocating in the
non-mappable portion of LMEM, on devices with small BAR.

v2(Thomas):
- The BO_ALLOC_TOPDOWN naming here is poor, since this is pure lies on
systems that don't even have small BAR. A better name is GPU_ONLY,
which is accurate regardless of the configuration.

Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Acked-by: Nirmoy Das <nirmoy.das@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220225145502.331818-3-matthew.auld@intel.com

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drm/i915: enforce min GTT alignment for discrete cards

For local-memory objects we need to align the GTT addresses
to 64K, both for the ppgtt and ggtt.

We need to support vm->min_alignment > 4K, de

drm/i915: enforce min GTT alignment for discrete cards

For local-memory objects we need to align the GTT addresses
to 64K, both for the ppgtt and ggtt.

We need to support vm->min_alignment > 4K, depending
on the vm itself and the type of object we are inserting.
With this in mind update the GTT selftests to take this
into account.

For compact-pt we further align and pad lmem object GTT addresses
to 2MB to ensure PDEs contain consistent page sizes as
required by the HW.

v3:
* use needs_compact_pt flag to discriminate between
64K and 64K with compact-pt
* add i915_vm_obj_min_alignment
* use i915_vm_obj_min_alignment to round up vma reservation
if compact-pt instead of hard coding
v5:
* fix i915_vm_obj_min_alignment for internal objects which
have no memory region
v6:
* tiled_blits_create correctly pick largest required alignment
v8:
* i915_vm_min_alignment protect against array overflow for mock region

Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
Signed-off-by: Robert Beckett <bob.beckett@collabora.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220218184752.7524-7-ramalingam.c@intel.com

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drm/i915: Allow dead vm to unbind vma's without lock.

i915_gem_vm_close may take the lock, and we currently have no better way
of handling this. At least for now, allow a path in which holding vm->m

drm/i915: Allow dead vm to unbind vma's without lock.

i915_gem_vm_close may take the lock, and we currently have no better way
of handling this. At least for now, allow a path in which holding vm->mutex
is sufficient. This is the case, because the object destroy path will
forcefully take vm->mutex now.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220128085739.1464568-1-maarten.lankhorst@linux.intel.com
Reviewed-by: Thomas Hellstrom <thomas.hellstrom@linux.intel.com>

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drm/i915: delete shadow "ret" variable

This "ret" declaration shadows an existing "ret" variable at the top of
the function. Delete it.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Revi

drm/i915: delete shadow "ret" variable

This "ret" declaration shadows an existing "ret" variable at the top of
the function. Delete it.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220127085115.GD25644@kili
Fixes: f6c466b84cfa ("drm/i915: Add support for moving fence waiting")

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drm/i915: Fix vma resource freeing

In some cases we use leftover kfree() instead of i915_vma_resource_free().
Fix this.

Fixes: 2f6b90da9192 ("drm/i915: Use vma resources for async unbinding")
Repor

drm/i915: Fix vma resource freeing

In some cases we use leftover kfree() instead of i915_vma_resource_free().
Fix this.

Fixes: 2f6b90da9192 ("drm/i915: Use vma resources for async unbinding")
Reported-by: Robert Beckett <bob.beckett@collabora.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220119174734.213552-1-thomas.hellstrom@linux.intel.com

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drm/i915: Flush TLBs before releasing backing store

We need to flush TLBs before releasing backing store otherwise userspace
is able to encounter stale entries if a) it is not declaring access to
ce

drm/i915: Flush TLBs before releasing backing store

We need to flush TLBs before releasing backing store otherwise userspace
is able to encounter stale entries if a) it is not declaring access to
certain buffers and b) it races with the backing store release from a
such undeclared execution already executing on the GPU in parallel.

The approach taken is to mark any buffer objects which were ever bound
to the GPU and to trigger a serialized TLB flush when their backing
store is released.

Alternatively the flushing could be done on VMA unbind, at which point
we would be able to ascertain whether there is potential a parallel GPU
execution (which could race), but essentially it boils down to paying
the cost of TLB flushes potentially needlessly at VMA unbind time (when
the backing store is not known to be going away so not needed for
safety), versus potentially needlessly at backing store relase time
(since we at that point cannot tell whether there is anything executing
on the GPU which uses that object).

Thereforce simplicity of implementation has been chosen for now with
scope to benchmark and refine later as required.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reported-by: Sushma Venkatesh Reddy <sushma.venkatesh.reddy@intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Dave Airlie <airlied@redhat.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jon Bloomfield <jon.bloomfield@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

drm/i915: Remove short-term pins from execbuf, v6.

Add a flag PIN_VALIDATE, to indicate we don't need to pin and only
protected by the object lock.

This removes the need to unpin, which is done by

drm/i915: Remove short-term pins from execbuf, v6.

Add a flag PIN_VALIDATE, to indicate we don't need to pin and only
protected by the object lock.

This removes the need to unpin, which is done by just releasing the
lock.

eb_reserve is slightly reworked for readability, but the same steps
are still done:
- First pass pins with NONBLOCK.
- Second pass unbinds all objects first, then pins.
- Third pass is only called when not all objects are softpinned, and
unbinds all objects, then calls i915_gem_evict_vm(), then pins.

Changes since v1:
- Split out eb_reserve() into separate functions for readability.
Changes since v2:
- Make batch buffer mappable on platforms where only GGTT is available,
to prevent moving the batch buffer during relocations.
Changes since v3:
- Preserve current behavior for batch buffer, instead be cautious when
calling i915_gem_object_ggtt_pin_ww, and re-use the current batch vma
if it's inside ggtt and map-and-fenceable.
- Remove impossible condition check from eb_reserve. (Matt)
Changes since v5:
- Do not even temporarily pin, just call i915_gem_evict_vm() and mark
all vma's as unpinned.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220114132320.109030-7-maarten.lankhorst@linux.intel.com

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drm/i915: Remove support for unlocked i915_vma unbind

Now that we require the object lock for all ops, some code handling
race conditions can be removed.

This is required to not take short-term pin

drm/i915: Remove support for unlocked i915_vma unbind

Now that we require the object lock for all ops, some code handling
race conditions can be removed.

This is required to not take short-term pins inside execbuf.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: Niranjana Vishwanathapura <niranjana.vishwanathapura@intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220114132320.109030-6-maarten.lankhorst@linux.intel.com

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drm/i915: Add i915_vma_unbind_unlocked, and take obj lock for i915_vma_unbind, v2.

We want to remove more members of i915_vma, which requires the locking to
be held more often.

Start requiring gem

drm/i915: Add i915_vma_unbind_unlocked, and take obj lock for i915_vma_unbind, v2.

We want to remove more members of i915_vma, which requires the locking to
be held more often.

Start requiring gem object lock for i915_vma_unbind, as it's one of the
callers that may unpin pages.

Some special care is needed when evicting, because the last reference to
the object may be held by the VMA, so after __i915_vma_unbind, vma may be
garbage, and we need to cache vma->obj before unlocking.

Changes since v1:
- Make trylock failing a WARN. (Matt)
- Remove double i915_vma_wait_for_bind() (Matt)
- Move atomic_set to right before mutex_unlock(), to make it more clear
they belong together. (Matt)

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.william.auld@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220114132320.109030-5-maarten.lankhorst@linux.intel.com

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drm/i915: Add object locking to i915_gem_evict_for_node and i915_gem_evict_something, v2.

Because we will start to require the obj->resv lock for unbinding,
ensure these vma eviction utility functio

drm/i915: Add object locking to i915_gem_evict_for_node and i915_gem_evict_something, v2.

Because we will start to require the obj->resv lock for unbinding,
ensure these vma eviction utility functions also take the lock.

This requires some function signature changes, to ensure that the
ww context is passed around, but is mostly straightforward.

Previously this was split up into several patches, but reworking
should allow for easier bisection.

Changes since v1:
- Handle evicting dead objects better.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220114132320.109030-4-maarten.lankhorst@linux.intel.com

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drm/i915: Add locking to i915_gem_evict_vm(), v3.

i915_gem_evict_vm will need to be able to evict objects that are
locked by the current ctx. By testing if the current context already
locked the obj

drm/i915: Add locking to i915_gem_evict_vm(), v3.

i915_gem_evict_vm will need to be able to evict objects that are
locked by the current ctx. By testing if the current context already
locked the object, we can do this correctly. This allows us to
evict the entire vm even if we already hold some objects' locks.

Previously, this was spread over several commits, but it makes
more sense to commit the changes to i915_gem_evict_vm separately
from the changes to i915_gem_evict_something() and
i915_gem_evict_for_node().

Changes since v1:
- Handle evicting dead objects better.
Changes since v2:
- Use for_i915_gem_ww in igt_evict_vm. (Thomas)

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
[mlankhorst: Fix up doc warning.]
Link: https://patchwork.freedesktop.org/patch/msgid/20220117075604.131477-1-maarten.lankhorst@linux.intel.com

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drm/i915: Use struct vma_resource instead of struct vma_snapshot

There is always a struct vma_resource guaranteed to be alive when we
access a corresponding struct vma_snapshot.

So ditch the latter

drm/i915: Use struct vma_resource instead of struct vma_snapshot

There is always a struct vma_resource guaranteed to be alive when we
access a corresponding struct vma_snapshot.

So ditch the latter and instead of allocating vma_snapshots, reference
the already existning vma_resource.

This requires a couple of extra members in struct vma_resource but that's
a small price to pay for the simplification.

v2:
- Fix a missing include and declaration (kernel test robot <lkp@intel.com>)

Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220110172219.107131-7-thomas.hellstrom@linux.intel.com

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drm/i915: Use vma resources for async unbinding

Implement async (non-blocking) unbinding by not syncing the vma before
calling unbind on the vma_resource.
Add the resulting unbind fence to the objec

drm/i915: Use vma resources for async unbinding

Implement async (non-blocking) unbinding by not syncing the vma before
calling unbind on the vma_resource.
Add the resulting unbind fence to the object's dma_resv from where it is
picked up by the ttm migration code.
Ideally these unbind fences should be coalesced with the migration blit
fence to avoid stalling the migration blit waiting for unbind, as they
can certainly go on in parallel, but since we don't yet have a
reasonable data structure to use to coalesce fences and attach the
resulting fence to a timeline, we defer that for now.

Note that with async unbinding, even while the unbind waits for the
preceding bind to complete before unbinding, the vma itself might have been
destroyed in the process, clearing the vma pages. Therefore we can
only allow async unbinding if we have a refcounted sg-list and keep a
refcount on that for the vma resource pages to stay intact until
binding occurs. If this condition is not met, a request for an async
unbind is diverted to a sync unbind.

v2:
- Use a separate kmem_cache for vma resources for now to isolate their
memory allocation and aid debugging.
- Move the check for vm closed to the actual unbinding thread. Regardless
of whether the vm is closed, we need the unbind fence to properly wait
for capture.
- Clear vma_res::vm on unbind and update its documentation.
v4:
- Take cache coloring into account when searching for vma resources
pending unbind. (Matthew Auld)
v5:
- Fix timeout and error check in i915_vma_resource_bind_dep_await().
- Avoid taking a reference on the object for async binding if
async unbind capable.
- Fix braces around a single-line if statement.
v6:
- Fix up the cache coloring adjustment. (Kernel test robot <lkp@intel.com>)
- Don't allow async unbinding if the vma_res pages are not the same as
the object pages. (Matthew Auld)
v7:
- s/unsigned long/u64/ in a number of places (Matthew Auld)

Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220110172219.107131-5-thomas.hellstrom@linux.intel.com

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drm/i915: Don't pin the object pages during pending vma binds

A pin-count is already held by vma->pages so taking an additional pin
during async binds is not necessary.

When we introduce async unbi

drm/i915: Don't pin the object pages during pending vma binds

A pin-count is already held by vma->pages so taking an additional pin
during async binds is not necessary.

When we introduce async unbinding we have other means of keeping the
object pages alive.

Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220110172219.107131-4-thomas.hellstrom@linux.intel.com

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drm/i915: Use the vma resource as argument for gtt binding / unbinding

When introducing asynchronous unbinding, the vma itself may no longer
be alive when the actual binding or unbinding takes place

drm/i915: Use the vma resource as argument for gtt binding / unbinding

When introducing asynchronous unbinding, the vma itself may no longer
be alive when the actual binding or unbinding takes place.

Update the gtt i915_vma_ops accordingly to take a struct i915_vma_resource
instead of a struct i915_vma for the bind_vma() and unbind_vma() ops.
Similarly change the insert_entries() op for struct i915_address_space.

Replace a couple of i915_vma_snapshot members with their newly introduced
i915_vma_resource counterparts, since they have the same lifetime.

Also make sure to avoid changing the struct i915_vma_flags (in particular
the bind flags) async. That should now only be done sync under the
vm mutex.

v2:
- Update the vma_res::bound_flags when binding to the aliased ggtt
v6:
- Remove I915_VMA_ALLOC_BIT (Matthew Auld)
- Change some members of struct i915_vma_resource from unsigned long to u64
(Matthew Auld)
v7:
- Fix vma resource size parameters to be u64 rather than unsigned long
(Matthew Auld)

Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220110172219.107131-3-thomas.hellstrom@linux.intel.com

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drm/i915: Initial introduction of vma resources

Introduce vma resources, sort of similar to TTM resources, needed for
asynchronous bind management. Initially we will use them to hold
completion of

drm/i915: Initial introduction of vma resources

Introduce vma resources, sort of similar to TTM resources, needed for
asynchronous bind management. Initially we will use them to hold
completion of unbinding when we capture data from a vma, but they will
be used extensively in upcoming patches for asynchronous vma unbinding.

v6:
- Some documentation updates

Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220110172219.107131-2-thomas.hellstrom@linux.intel.com

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drm/i915: split out gem/i915_gem_tiling.h from i915_drv.h

We already have the gem/i915_gem_tiling.c file.

Acked-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Jani Nikula <jani.nikula

drm/i915: split out gem/i915_gem_tiling.h from i915_drv.h

We already have the gem/i915_gem_tiling.c file.

Acked-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/8073a429ed1f8ade9c0cc8a6ed1a0f82183100c5.1641561552.git.jani.nikula@intel.com

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drm/i915: split out i915_gem_evict.h from i915_drv.h

We already have the i915_gem_evict.c file.

v2: Fixed commit message (Tvrtko)

Acked-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by:

drm/i915: split out i915_gem_evict.h from i915_drv.h

We already have the i915_gem_evict.c file.

v2: Fixed commit message (Tvrtko)

Acked-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/ec666853171d04daeb21a93083940df36907c343.1641561552.git.jani.nikula@intel.com

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drm/i915: Require the vm mutex for i915_vma_bind()

Protect updates of struct i915_vma flags and async binding / unbinding
with the vm::mutex. This means that i915_vma_bind() needs to assert
vm::mute

drm/i915: Require the vm mutex for i915_vma_bind()

Protect updates of struct i915_vma flags and async binding / unbinding
with the vm::mutex. This means that i915_vma_bind() needs to assert
vm::mutex held. In order to make that possible drop the caching of
kmap_atomic() maps around i915_vma_bind().

An alternative would be to use kmap_local() but since we block cpu
unplugging during sleeps inside kmap_local() sections this may have
unwanted side-effects. Particularly since we might wait for gpu while
holding the vm mutex.

This change may theoretically increase execbuf cpu-usage on snb, but
at least on non-highmem systems that increase should be very small.

Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211221200050.436316-5-thomas.hellstrom@linux.intel.com

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drm/i915: Take object lock in i915_ggtt_pin if ww is not set

i915_vma_wait_for_bind needs the vma lock held, fix the caller.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Rev

drm/i915: Take object lock in i915_ggtt_pin if ww is not set

i915_vma_wait_for_bind needs the vma lock held, fix the caller.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211216142749.1966107-5-maarten.lankhorst@linux.intel.com

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drm/i915: Remove pages_mutex and intel_gtt->vma_ops.set/clear_pages members, v3.

Big delta, but boils down to moving set_pages to i915_vma.c, and removing
the special handling, all callers use the d

drm/i915: Remove pages_mutex and intel_gtt->vma_ops.set/clear_pages members, v3.

Big delta, but boils down to moving set_pages to i915_vma.c, and removing
the special handling, all callers use the defaults anyway. We only remap
in ggtt, so default case will fall through.

Because we still don't require locking in i915_vma_unpin(), handle this by
using xchg in get_pages(), as it's locked with obj->mutex, and cmpxchg in
unpin, which only fails if we race a against a new pin.

Changes since v1:
- aliasing gtt sets ZERO_SIZE_PTR, not -ENODEV, remove special case
from __i915_vma_get_pages(). (Matt)
Changes since v2:
- Free correct old pages in __i915_vma_get_pages(). (Matt)
Remove race of clearing vma->pages accidentally from put,
free it but leave it set, as only get has the lock.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211216142749.1966107-4-maarten.lankhorst@linux.intel.com
Reviewed-by: Matthew Auld <matthew.auld@intel.com>

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