drm/i915/ttm: fix 32b build

Since segment_pages is no longer a compile time constant, it looks the
DIV_ROUND_UP(node->size, segment_pages) breaks the 32b build. Simplest
is just to use the ULL variant, but really we should need not need more
than u32 for the page alignment (also we are limited by that due to the
sg->length type), so also make it all u32.

Reported-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Fixes: bc99f1209f19 ("drm/i915/ttm: fix sg_table construction")
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Nirmoy Das <nirmoy.das@linux.intel.com>
Reviewed-by: Nirmoy Das <nirmoy.das@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220712174050.592550-1-matthew.auld@intel.com

drm/i915/ttm: fix sg_table construction

If we encounter some monster sized local-memory page that exceeds the
maximum sg length (UINT32_MAX), ensure that don't end up with some
misaligned address in the entry that follows, leading to fireworks
later. Also ensure we have some coverage of this in the selftests.

v2(Chris):
- Use round_down consistently to avoid udiv errors
v3(Nirmoy):
- Also update the max_segment in the selftest

Fixes: f701b16d4cc5 ("drm/i915/ttm: add i915_sg_from_buddy_resource")
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/6379
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Nirmoy Das <nirmoy.das@linux.intel.com>
Reviewed-by: Nirmoy Das <nirmoy.das@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220711085859.24198-1-matthew.auld@intel.com

drm/i915/ttm: fix 32b build

Since segment_pages is no longer a compile time constant, it looks the
DIV_ROUND_UP(node->size, segment_pages) breaks the 32b build. Simplest
is just to use the ULL variant, but really we should need not need more
than u32 for the page alignment (also we are limited by that due to the
sg->length type), so also make it all u32.

Reported-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Fixes: aff1e0b09b54 ("drm/i915/ttm: fix sg_table construction")
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Nirmoy Das <nirmoy.das@linux.intel.com>
Reviewed-by: Nirmoy Das <nirmoy.das@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220712174050.592550-1-matthew.auld@intel.com
(cherry picked from commit 9306b2b2dfce6931241ef804783692cee526599c)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drm/i915/ttm: fix sg_table construction

If we encounter some monster sized local-memory page that exceeds the
maximum sg length (UINT32_MAX), ensure that don't end up with some
misaligned address in the entry that follows, leading to fireworks
later. Also ensure we have some coverage of this in the selftests.

v2(Chris):
- Use round_down consistently to avoid udiv errors
v3(Nirmoy):
- Also update the max_segment in the selftest

Fixes: f701b16d4cc5 ("drm/i915/ttm: add i915_sg_from_buddy_resource")
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/6379
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Nirmoy Das <nirmoy.das@linux.intel.com>
Reviewed-by: Nirmoy Das <nirmoy.das@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220711085859.24198-1-matthew.auld@intel.com
(cherry picked from commit bc99f1209f19fefa3ee11e77464ccfae541f4291)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drm/i915/ttm: wire up the object offset

For the ttm backend we can use existing placements fpfn and lpfn to
force the allocator to place the object at the requested offset,
potentially evicting stuff if the spot is currently occupied.

Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Nirmoy Das <nirmoy.das@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220315181425.576828-5-matthew.auld@intel.com

drm/i915/ttm: Drop region reference counting

There is an interesting refcounting loop:
struct intel_memory_region has a struct ttm_resource_manager,
ttm_resource_manager->move may hold a reference to i915_request,
i915_request may hold a reference to intel_context,
intel_context may hold a reference to drm_i915_gem_object,
drm_i915_gem_object may hold a reference to intel_memory_region.

Break this loop by dropping region reference counting.

In addition, Have regions with a manager moving fence make sure
that all region objects are released before freeing the region.

v6:
- Fix a code comment.

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/20211122214554.371864-4-thomas.hellstrom@linux.intel.com

drm/i915: Introduce refcounted sg-tables

As we start to introduce asynchronous failsafe object migration,
where we update the object state and then submit asynchronous
commands we need to record what memory resources are actually used
by various part of the command stream. Initially for three purposes:

1) Error capture.
2) Asynchronous migration error recovery.
3) Asynchronous vma bind.

At the time where these happens, the object state may have been updated
to be several migrations ahead and object sg-tables discarded.

In order to make it possible to keep sg-tables with memory resource
information for these operations, introduce refcounted sg-tables that
aren't freed until the last user is done with them.

The alternative would be to reference information sitting on the
corresponding ttm_resources which typically have the same lifetime as
these refcountes sg_tables, but that leads to other awkward constructs:
Due to the design direction chosen for ttm resource managers that would
lead to diamond-style inheritance, the LMEM resources may sometimes be
prematurely freed, and finally the subclassed struct ttm_resource would
have to bleed into the asynchronous vma bind code.

v3:
- Address a number of style issues (Matthew Auld)
v4:
- Dont check for st->sgl being NULL in i915_ttm_tt__shmem_unpopulate(),
that should never happen. (Matthew Auld)
v5:
- Fix a Potential double-free (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/20211101122444.114607-1-thomas.hellstrom@linux.intel.com

drm/i915/ttm: remove node usage in our naming

Now that ttm_resource_manager just returns a generic ttm_resource we
don't need to reference the mm_node stuff anymore which mostly only
makes sense for drm_mm_node. In the next few patches we want switch over
to the ttm_buddy_man which is just another type of ttm_resource so
reflect that in the naming.

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>
Link: https://patchwork.freedesktop.org/patch/msgid/20210616152501.394518-5-matthew.auld@intel.com

drm/i915/ttm: Calculate the object placement at get_pages time

Instead of relying on a static placement, calculate at get_pages() time.
This should work for LMEM regions and system for now. For stolen we need
to take preallocated range into account. That will if needed be added
later.

Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210616152501.394518-3-matthew.auld@intel.com

drm/i915/ttm: Introduce a TTM i915 gem object backend

Most logical place to introduce TTM buffer objects is as an i915
gem object backend. We need to add some ops to account for added
functionality like delayed delete and LRU list manipulation.

Initially we support only LMEM and SYSTEM memory, but SYSTEM
(which in this case means evicted LMEM objects) is not
visible to i915 GEM yet. The plan is to move the i915 gem system region
over to the TTM system memory type in upcoming patches.

We set up GPU bindings directly both from LMEM and from the system region,
as there is no need to use the legacy TTM_TT memory type. We reserve
that for future porting of GGTT bindings to TTM.

Remove the old lmem backend.

Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210610070152.572423-2-thomas.hellstrom@linux.intel.com

drm/i915/ttm Initialize the ttm device and memory managers

Temporarily remove the buddy allocator and related selftests
and hook up the TTM range manager for i915 regions.

Also modify the mock region selftests somewhat to account for a
fragmenting manager.

Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210602083818.241793-2-thomas.hellstrom@linux.intel.com